LIBRARY OF CONGRESS. 
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UNITED- SIA-TES JOS AMERICA. 



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THE 



SLIDE VALVE 

PRACTICALLY EXPLAINED. 



EMBRACING 



SIMPLE AND COMPLETE PRACTICAL DEMONSTRATIONS OF THE OPER- 
ATION OP EACH ELEMENT IN A SLIDE-VALVE MOVEMENT, AND 
ILLUSTRATING THE EFFECTS OF VARIATIONS IN THEIR 
PROPORTIONS, BY EXAMPLES CAREFULLY 
SELECTED FROM THE MOST RECENT 
AND SUCCESSFUL PRACTICE. 



BY 

JOSHUA KOSE, M.E., 

Author of " The Complete Practical*Machinist," •« The Pattern Maker' 
Assistant," etc. etc. 




ILLUSTRATED BY 35 ENGRAVINGS. 



T/60C' 



PHILADELPHIA: 

HENRY CAREY BAIRD & CO., 

Industrial Publishers, Booksellers, and Importers, 
810 WALNUT STREET. 

1880. 






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Copyright by 
HENKY CARET BAIED & CO. 

1SS0. 



COLLINS, PRINTER. 




PREFACE. 



The object of this book is to present to practical men a 
clear explanation of the operations of a slide valve under the 
conditions in •which it is found in actual practice. The 
author believes that its clear and concise treatment of the 
subject will leave nothing to be desired, even by those who 
begin it in entire ignorance of the subject matter. 



CONTENTS 



PAOE 

Simplest form of valve .5 

Lead and its effects * 7 

Diagram of simple valve action 11 

Steam lap explained .13 

Diagram showing effects of steam lap . . . .17 
The angularity of the connecting rod and its effect on the 

valve action 18 

The eccentric piston and crank movements . . .21 
Exhaust lap explained . . . . .25 

Diagram showing effects of exhaust lap . . . .28 
Clearance explained ........ 30 

Effects of clearance .31 

Valve travel considered 32 

Effect of over travel on the position of the eccentric and 

port openings . . . .34 

Point of cut-off . .37 

The rock shaft and its effect on the position of the eccen- 
tric and on the distribution of the steam . . .40 

Examples from practice 44 

Comparison of the merits of the various examples . . 57 

Comparison of port areas 58 

" compression . . . . . .59 

" expansion CO 

" exhaust areas . . . . . .61 

1* (v) 



CONTENTS. 



PAQB 

Comparison of valves of exhaust areas . . .62 

11 ports to their duty ..... 64 

" areas of wearing surface . . . .67 

Rules for areas of steam ports 69 

Shapes of ports 72 

Power required to operate valve 76 

Conditions as affecting friction ...... 77 

"Warping of valves 80 

Spring of valves from pressure 81 

Coefficient of friction 84 

Practical experiment on friction 87 

Size of valve as affecting friction . . . . . 88 

Lubrication of slide valves 88 

Ascertaining with a pair of compasses the result to be 

obtained from a given slide valve 89 

To ascertain point of full steam port opening . . .90 
" position of piston when port is full open . 90 

" point at which valve begins to close . . 90 

" point of cutoff 92 

" amount of expansion 92 

" point of release .92 

" point at which exhaust begins . . .93 

" point of full exhaust opening . . .93 

M point where cushioning began . . .93 

" amount of cushioning 93 

To set a single eccentric without moving the engine . 95 
" a double eccentric without moving the engine .' 96 
" eccentrics when the rod is not in line with the 
cylinder bore ......... 97 



THE SLIDE VALVE. 



WITHOUT LAP. 

The simple term slide valve is understood to mean a single 
valve such as is shown in Fig. 1. Devices which have a 
second valve for the purpose of cutting off the steam supply 
or for the exhaust, are distinguished hy a second appellation 
denoting the object of the design or the action of the valves, 
as "cut off slide valve," "automatic cut-off slide valve," etc. 
etc. The slide valve is in universal use for locomotives and 
small stationary and boat engines, but has been largely re- 
placed in large stationary engines by automatic cut-off valves. 

In some cases a steam engine cylinder has its slide valve 
motion constructed in two divisions, a steam port and an ex- 
haust port at each end of the cylinder, the two valves being 
connected together by a rod. The object of this arrangement 
is to obtain short steam passages ; but since the action of the 
valve is precisely the same as if the two valves were consoli- 
dated into one, as in all our examples, no attention need be 
given to them. 

The simplest form in which the slide valve is made, is that 
shown in Fig. 1, in which A represents the steam port for one, 
and B, the steam port for the other end of the cylinder, while 

(5) 



6 

C represents the cylinder exhaust port ; DD, the bridges ; E, 
the slide valve, and F, the valve exhaust port. The valve, is 
shown in the position in which it stands when the piston is at 







the end, G^ of the cylinder ; the port A, acting as a steam 
port that is to admit steam from the steam chest into the cyl- 
inder. The steam in the cylinder in the side, H, of the piston 
(which steam propelled the engine the previous stroke) now 



finds egress through the port, B, and thence through F and 
to the exhaust pipe. 

The valve after traveling in the direction of the arrow, J y 
until it leaves the port, A, full open, reverses its motion and 
travels back, closing the port, A, and opening, B, to the steam 
in the steam chest. It will be noted that there is shown a 
slight opening left by the valve to the port, A, and the amount 
of this opening when the piston is at the exact end of its stroke 
is called the lead of the valve. The action of lead is three- 
fold ; first, it admits steam to the piston before it has arrived 
at the end of the stroke, and this steam acts as a cushion, 
causing the piston, etc., to reverse its motion easily. Sec- 
ondly, it assists the admission of the steam, tending to per- 
mit the steam passage to become supplied with steam at the 
steam chest pressure by the time the piston reverses its mo- 
tion ; and, thirdly, it assists the exhaust in its early part, 
which is of especial importance to a valve such as is shown 
in Fig. 1. 

If the valve had no lead it would stand so as to just close 
the two ports, A and B, when the piston stood at either end of 
the stroke, and then while the piston made a stroke the valve 
would move so as to first open and then close the requisite port. 
Suppose, for example, the piston shown in Fig. 1 were to make 
a stroke ; while it was doing so, the valve would move in the 
direction of the arrow, J, until it left the port, A, wide open, 
whereupon, it would travel back and reclose that port, arriving 
at the precise position from which it started at the same instant 
that the piston terminated its stroke. It will be noted that 
precisely as the port, A, opens as a steam port, the port, B, 
opens as an exhaust port, and vice versa, so that while C and 
.F always act as exhaust ports, A and B act alternately and re- 
spectively as steam and exhaust ports, the lead of the valve 
acting the same at each end of the stroke, that is, opening the 
steam port on one side and the exhaust port on the other side 



8 

of the piston in advance of the piston arriving at the terminal 
of its stroke. The lead of the valve is determined by the po- 
sition of the eccentric. In Fig. 2, a A represents the center 
line of the crank, and c the throw line of the eccentric, the line; 
E, representing an imaginary line, standing at a right angle 
to a A. Now if the eccentric stood so that its throw line 
was at a right angle to the center line, a Aoi the crank, it 




would have no lead, or angular advance, as it is sometimes 
termed, and hence, the valve would have no lead. Suppos- 
ing, however, the crank in Fig. 2 to revolve in the direction 
of the arrow, by moving the eccentric forward (that is in the 
direction in which the crank is to revolve) so that its throw 
line stands in advance of a line intersecting the center of the 
crank-shaft, and at a right angle to the center-line, a A, of the 
crank a valve may be given any desired amount of leadi 



9 

The angular advance or lead of the eccentric shown in Fig.2 
being the distance between c and E. In American locomo- 
tive practice, the amount of lead given varies from about 
3-32d to 3-16th inch, while in English, practice it is gene- 
rally more, ranging from 3-32d to ^th-inch. In stationary 
cut-off engine practice, from l-64th to ^th-inch lead is the 
usual proportion, and in many cases not more than l-64th- 
inch is employed. If a valve is given exhaust lap, a portion 
of the exhaust steam is enclosed in the cylinder, and acts both, 
to cushion the piston and fill the passages with steam at a 
pressure, the difference between its action and that of the lead 
being that the former renders the exhaust less free, while the 
latter assists it. Since, however, a valve having no steam lap 
is apt (unless its movement is a very slow one) to have a 
cramped exhaust, lap on the exhaust side is inadmissible in 
such valves and the subject need not, in this connection, be 
discussed. 

The objections to the use of a valve such as shown in Fig. 
1, are that it does not cut off the steam supply before the pis 
ton has arrived at the end of its stroke, and the steam in the 
cylinder is not used expansively, and, therefore, not econo- 
mically. Then, again, the admission and exhaust of the 
steam to and from the cylinder, takes place slowly, with the 
result that neither occurs freely until the piston has traveled 
some distance. To demonstrate the effect of such a valve it 
will be well to introduce the form of diagram it is intended to 
employ to illustrate the operation of the various forms of 
valves to be hereafter considered. 

Let us suppose, then, that we have in our possession an 
engine of 24-inches stroke, the connecting rod being three 
times the length of the stroke ; the valve elements being as 
follows : — "Width of steam ports, 1-inch ; width of bridge 
finch ; width of exhaust port 1-inch ; lap 0, lead l-16th inch; 
travel of valve 2 inches. Then starting from the end of the 



10 

stroke nearest to the crank, we move the engine piston an 
inch, and measure how much the steam-port is open ; then 
after moving the piston another inch of the stroke, we again 
measure the amount the steam-port is open, making in each 
case a note of the data thus obtained, and continuing the 
operation through a full revolution of the engine, and noting 
down the position of the valve on both the steam and ex- 
haust ports respectively. From the data thus obtained, we 
construct our diagram, as follows : — We draw the line, A, B, 
in Fig. 3, which represents the length of the engine stroke ; 
this line we divide off into as many equal divisions as there 
are inches in the piston stroke, so that each line denoting a 
division will denote an inch of piston movement. Above 
this line, AB, we draw the parallel line, c c, the distance be- 
tween the two lines being the exact width of the steam ports 
of our engine. The line, B D, is next drawn, parallel also 
with A B, but below it to an amount equal to the width of 
the steam port. The lines at right angles to the line, AB, 
and representing the inches in the engine stroke, being 
drawn to intersect, respectively, the three parallel lines A B, 
c c, and D D, we take our data of the piston and valve 
movements, and proceed as follows : — Beginning at A, we 
make a mark above it, a distance equal to the amount of lead 
on the valve of our engine, then passing to the next line 
(above the line A B,) we make thereon another mark, its dis- 
tance or height from A B, being the amount that our data 
show the valve was open when the engine piston had moved 
an inch. This process we continue until we arrive at the 
24th line, and then a line drawn through all the marks so 
made will show at a glance how the port was opened for 
the admission of the steam. Then turning to our data, we 
mark, in like manner, on the lines from 1 to 24, respective- 
ly, but below the line A B, and beginning at the right hand, 
the width the exhaust port stood open from the 1st to 



11 



the 24th inch of the exhaust, and drawing a line through 
these points will denote exactly how the port opened and 
closed during the exhaust of the steam. Thus, then, we 




have a record of the admission and exhaust for one stroke of 
the engine, or, in other words, of the admission and exhaust 
of the steam through the port nearest to the crank end of 
the cylinder. We then go through the same process, using 
2 



12 

the data obtained by the other stroke of the engine piston ; 
but in this case we leave the dots intact instead of drawing 
a line through them, and thus we not only distinguish one 
diagram from the other, but we are afforded an excellent op- 
portunity to perceive and compare the difference in the action 
of the valve during one stroke as compared with the next. 
Thus on referring to Fig. 3, we read that during one stroke, 
the port did not open full as a steam port until the piston 
had traveled more than eleven inches of the stroke, while 
during the other stroke it stood full open at the tenth inch of 
the stroke. Then we find that the exhaust was full open for 
one stroke at the ninth inch of the piston movement, and [for 
the other stroke at the thirteenth inch. "We may also readily 
observe that on the stroke in which the valve opened the 
slowest tor the admission, it opened the quickest for the ex- 
haust of the steam, and if we desire to know how wide open 
the port stood at any particular inch of the stroke, we have 
but to measure the length of the vertical line referring to 
that inch of the stroke. For example, when the piston was 
moving away from the crank, the port at the seventh and 
twenty -first inches of the piston movement stood open |-inch 
and finch, respectively (as marked upon the diagram), or 
during the other stroke of the piston the port stood open as a 
steam port f -inch, when the piston had moved 3 inches, and 
stood open finch as an exhaust port, when the piston had 
moved 4 inches of the return or exhaust stroke. 



13 



STEAM LAP, OR LAP ON THE STEAM SIDE OF 
THE VALVE. 

In all engines in which the slide valve is operated by a 
revolving eccentric, the valve should have what is termed 
steam lap, for although without this lap the steam at about 
steam-chest pressure will follow the piston for the full length 
of the stroke, as shown in Fig. 3, yet the engine will exert 
less power than it would if by means of steam lap the steam 
supply were cut off at some point before the piston arrived at 
the end of the stroke. At what particular point this will be 
in any given engine will depend upon the speed at which the 
engine runs, but in any event the faster the engine runs the 
earlier in the stroke should the steam supply be cut off to ob- 
tain the maximum of power from the engine. Now especially 
is this the case if the valve have but little or no lead. The 
reason of this is, that with a minimum of lead and no steam 
lap, the steam on the exhaust side of the piston cannot escape 
quickly enough to prevent its exerting a back pressure on the 
piston. 

The lap of a valve is the amount by which it overlaps the 
cylinder steam ports when it stands in mid-position ; thus, in 
Fig. 4 the lap is the distance from A to B on one side and 
from C to D on the other side. 

When the word lap is used unaccompanied by the terms 
steam or exhaust, it is understood to refer to Tap on the steam 
side of the valve (as shown in Fig. 4), because while nearly all 
valves have steam lap, a majority of them have no exhaust 



14 

lap. So, likewise, the edges E, E, of the valve (Fig. 4) are 
called the steam edges, because they operate to admit or cut off 
the steam to and from the cylinder ports, and are at all times 
isolated from the exhaust ports. The edges F,F (Fig. 4) of 
the valve are called the exhaust edges because they operate 
to open or close the exhaust of the steam from the cylinder. 
The lap is usually measured on one side of the valve only ; thus, 
if (in Fig. 4) the valve measured an inch from A to B and an 
inch from G to D, it would be said to have an inch of lap, or 
an inch of steam lap, both terms signifying the same thing. 




The object of the steam lap is to cut off the supply of steam 
from the steam chest into the cylinder before the piston 
has completed its stroke, and the point in the stroke at which 
the supply is cut off, is called the point of cut-off. 

By using the steam expansively a more useful effect is ob- 
tained from it than would otherwise be the case. Suppose 
for example that the steam is exhausted from a high pressure 
engine cylinder at a pressure of 40 lbs. per square inch, and 
that the pressure of steam in the boiler was 75 lbs. per square 
inch, then it is evident that the fuel consumed in order to 
convert the feed-water into steam up to a pressure of 40 lbs. 
per square inch (the exhaust pressure) is not represented 
by any power imparted to the piston. Another way to view 



15 

the gain due to expansion is to suppose a piston having a 
stroke of 24 inches to receive steam from the steam chest dur- 
ing the first 12 inches of its stroke only, then while it is travel- 
ing the last 12 inches the steam in the cylinder will expand 
and still impart power to the piston, and this power constitutes 
the gain due to working the steam expansively, since it was ob- 
tained without the expenditure of any steam from the steam 
chest other than that necessary to fill the the cylinder during 
the first 12 inches of the piston stroke. It follows, then, that 
the steam is used the most economically when it is exhausted 
from the cylinder at a pressure equal to that of the atmosphere. 



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In Fig. 5, the valve is shown in the position in which it cuts 
off the steam supply to the cylinder, the piston and the valve 
traveling respectively in the direction denoted by the arrows, 
and the steam occupying that portion of the cylinder from 
A to B. 

Another and important object gained by giving a valve 
2* 



16 

steam lap is the obtainance of a free exhaust, which is of 
great importance, especially in a fast running engine. What- 
ever the amount of steam lap is, to that extent will it cause the 
valve (supposing it to have no exhaust lap) to leave the ex. 
haust port open when the piston is at the end of its stroke. If, 
for instance, we suppose the piston in Fig. 5 to be at the end, 
A, of the cylinder, then the valve would be in the same posi- 
tion, but traveling in the opposite direction, to that denoted 
by the arrow, and the port G, would be on the point of open 
ing as a steam port, while the port, D, would be acting as an 
exhaust port, and the latter, instead of being, closed as was 
the valve shown in Fig. 1, would be open, as shown in Fig. 5. 
In addition to this, however, the valve having lap must, 
in order to let the steam ports open full, necessarily have a 
proportionate increase of travel, and this again helps to give 
freedom to the exhaust steam by keeping the exhaust port 
open during a greater portion of the stroke. In like manner 
the increase of valve travel causes the valve to open the 
steam port quicker, giving a more ready supply of steam to 
the cylinder. 

For example, in Fig. 1 was shown a valve having no lap 
and in Fig. 3 was shown a diagram demonstrating the open- 
ing or closure of the steam and exhaust ports. In Fig. 5 is 
shown a similar valve with steam lap added. The propor- 
tions being : Width of steam ports 1 in. ; width of bridges 
\ in. ; width of exhaust port 2 in. ; steam lap | in. ; exhaust 
lap 0; travel of valve 3^ in. 

The only variations between these dimensions and those of 
the valve shown in Fig. 1, are that f-inch steam lap has been 
added, and, as a consequence, the cylinder exhaust port has 
been widened. 

In Fig. 6 is shown a diagram of the above valve, obtained, 
as before, by measuring the ports at each inch of piston move 
ment, the full lines being for the cylinder port farthest from 



the crank, and the dotted lines being for the port nearest to 
the crank. 




It will be observed, from this diagram, that the port nearest 
the crank obtained its maximum of opening as a steam port 
at the seventh inch of piston movement, but that it did not 
open to its fall extent (the reason of this will be shown fur- 
ther on). It commenced to perceptibly reclose at the ninth 
inch of piston movement — the expansion began at 19£ and 
ended at 223 — an a that the port opened as an exhaust port f 
in. by the time the piston completed its stroke. As an exhaust 
port, it remained full open until the sixteenth-inch of piston 
movement, the cushioning at the 22d inch and the lead be- 
ginning to open close to the end of the stroke. 



18 

Now comparing the operation of this port to that of the 
other cylinder steam port (as denoted by the dotted diagram), 
we observe that it opened slower and remained open longer, 
it used the steam less expansively, the exhaust closed earlier, 
and the cushioning was greater. And furthermore, comparing 
the difference between the port openings during the two pis- 
ton strokes with that shown in the diagram in Fig. 3, we find 
it a great deal more in this case. 



I £- 




THE ANGULARITY OF THE CONNECTING ROD. 

Suppose that in Fig. 7, the point, I, represents the dia- 
metrical center of a cross -head journal, and that the dotted 
circle represents the path of the center of the crank-pin. 
From A to B, then, will represent the first quarter-revolution 
of the crank (the figures from 1 to 4 denoting the respective 
quarter crank movements). The length of the line, J, from 
the center of the crank-shaft to the point, I", will represent 
the length of the connecting rod ; and if, setting a pair of com- 
passes to this length, and using the point, I, as a center, we 



19 

mark the arc, K, it becomes evident that the point at the 
junction of the arc, K, with the dotted circle, is the point at 
which the center of the crank-pin will stand when the piston 
is in the middle of its stroke, and it follows that by the time 
that the crank has made a full quarter revolution (from A to 
B) the piston will have traveled more than half its stroke to 
an amount that is dependent upon the proportion existing be- 
tween the length of the crank and that of the connecting rod, 
and the greater the relative length of the latter the less will 
that amount be. In the case under consideration, the stroke 
being 24 inches ana the connecting rod 72 inches long, the 
piston wii) have traveled three quarters of an inch more than 
half of its stroke by the time that the crank has made its first 
quarter revolution, and it follows that during the second 
quarter crank-revolution the piston will travel less than half 
its stroke. For the third quarter crank revolution the piston 
movement will be the same in amount as it was during the 
second, and for the fourth the same as during the first. 

The speed of the crank being uniform, it follows that that 
of the piston is irregular, and no matter in which direction the 
engine is running, the piston will travel relatively the fastest 
during each of the half-strokes performed between the end 
farthest from the crank and the middle of the cylinder. Sup- 
pose then that the opening and closure of the valve were 
performed uniform for each piston stroke, and that the crank 
made a half-revolution, starting from A in Fig. 7, traveling in 
the direction of the arrow and arriving at G. The speed of the 
piston being excessive during the first quarter crank move- 
ment, the opening permitted by the valve during that quarter 
revolution for the live steam to pass through is less in propor- 
tion to the piston movement than it should be. Now let us 
take the return stroke; while the crank is traveling from 
C to J), the piston will be moving below its average speed, 
and the port opening for the supply of steam being allowed aa 



20 

uniform for each stroke, the supply of steam will be greater 
in proportion to the piston movement. 

If we turn to the diagram shown in Fig. 3, we shall find 
this variation shown very plainly, and yet very minutely ; 
the egg-shaped diagram in full lines being the roundest on 
the right-hand side, which represents the end of the cyl- 
inder nearest to the crank. Confining ourselves to the half 
of the full line diagram above the line, A B, we find that the 
part of its length from 1 to 12f , which represents the port- 
opening during the first quarter crank movement, we find it 
more oval-shaped than it is from 12| to 24, representing the 
second quarter crank movement, and the difference between 
the shapes of the two represents the precise difference arising 
from the varying piston movement, which is caused by the 
angularity of the connecting rod. Examining the effect of 
this angularity of rod upon the same port acting as an ex- 
haust port, we find, from the part of the full line diagram 
below the line, A B, that the same irregularity exists, 
the only difference being that while it operated to diminish 
the opening of the port as a steam-port, it increased it as an 
exhaust port in a precisely similar ratio. 

Turning now to the diagram shown in Fig. 6, we find that, 
although the relative lengths of the crank and connecting rod 
remained unchanged, yet the above conditions are reversed, 
for, whereas the diagram in Fig. 3 showed that the port (re- 
presented by the full line) acting as a steam port opened 
slower than it closed, that represented in Fig. 6 by the full 
lines (both representing the corresponding piston stroke) 
opened quicker than it closed. On the exhaust side (in both 
diagrams), however, it opened quicker than it closed, this 
effect being produced directly from the alterations made in 
the cylinder exhaust port — the valve — and the throw and lead 
of the eccentric, and influenced indirectly from varying the 
relations of these elements to the angularity of the connecting 
rod. 



21 



THE ECCENTRIC, PISTON AND CRANK MOVE- 
MENTS. 

The action of an eccentric movement converted into a re- 
ciprocating one is irregular, in the same proportion and for the 
same reasons already explained with reference to the crank 
and piston movement. In Fig. 8 is represented a crank and 
an eccentric, both being shown in position to commence the 
first quarter revolution, and it will be noted that while the 
angularity of the connecting rod will cause the piston to 
move, during the quarter crank revolution, at its quickest 



^i~ 




speed, the position of the eccentric is such that it will cause 
the angularity of the eccentric rod to diminish the valve 
travel during the greater part of the eccentric quarter revolu- 
tion, for while the crank travels from A to B, in Fig. 8, the 
throw line of the eccentric will move from E to F. During 
this quarter revolution the valve is acting to open the steam- 
port (for the piston stroke under consideration) and hence the 
angularity of the eccentric rod is producing an effect the re- 



23 

verse of that due to the increase of valve travel, or in other 
words, the increase in the speed of the valve travel due to the 
increase of eccentric throw (necessitated by the use of the lap 
on the valve) is being modified by reason of the angularity 
of the eccentric rod. 

During the second quarter crank revolution the angularity 
of the connecting rod will cause the piston to travel slower 
than during the first, while the angularity of eccentric rod 
will act to increase the valve travel during the greater part, 
and slightly diminish during the latter part, of the quarter re- 
volution. 

Turning now to the return piston stroke (the crank starting 
from the point C) the angularity of the connecting rod will 
act to retard the piston movement during the first quarter re- 
volution, while that of the eccentric rod will act (mainly) to 
increase the valve travel (but to diminish it towards the last). 
While during the last quarter-crank movement the accelera- 
tion of piston speed will be accompanied by an (in the main) 
accelerated valve travel. 

The most salient points to be here considered are that, when 
the piston is traveling fast and hence requires the greatest sup- 
ply of steam, the opening of the port is the slowest, and vice 
versa, the effect being evidenced by the variation or distance 
between the full line and the dotted diagrams, in both Figs. 
3 and 6. The object of drawing the diagrams one over the 
other, and distinguishing one of them by dotted lines, is for 
the especial purpose of making plainly visible and easily com- 
parable the valve action, during one stroke as compared to the 
other, the effect due to the angularity of the connecting rod— 
the lap of the valve— and the travel of the valve being shown 
by the shape of the whole diagram on the left-hand side as com- 
pared to that of the right-hand side, and the effect of the lead 
of the eccentric being denoted by the variation between the 
shape of the full line and the dotted diagram. 



In making a comparison, however, it must be remembered 
that the middle of the diagram is at the 12| division on the 
upper or steam side, and 11^ division at the lower or exhaust 
side of the diagram, those points representing, respectively, 
the points at which the crank stands at a right angle to the 
connecting rod, or in other words, at half-throw. 

It will be noted from the full line diagram in Fig. 6, that 
the port there represented never opened quite full as a 
steam port, and this always occurs when the valve is given 
lap, the deficiency increasing with the lap. It must also be re- 
membered that during the opening of this port as a steam- 
port the piston speed is accelerated from the angularity of the 
connecting rod. To obviate this irregularity, the valve isoften 
given more travel by increasing the throw of the eccentric ; 
hence, examples with such increase will in due time be given. 

It will also be seen, on referring to Fig. 6, that the expan- 
sion began at the 19| inch of piston movement and ended at 
the 22| inch in one case, while in the other stroke it began at 
the 18th inch and ended at 22£ inch, and hence, that the 
steam was used expansively during three inches of one 
stroke and four and a quarter of the other. The exhaust also 
was unequal, taking place half an inch earlier for one stroke 
than for the other, and this distorted action always attends the 
employment of steam lap and increases in proportion to or 
with the lap, as will be shown in future examples of valve 
movements. 

In further reviewing the port opening in relation to the 
piston travel, it must be borne in mind, that it is during the 
travel of the piston from the dead-center to about the third 
of its stroke, that a free port-opening is of the most import- 
ance, and more especially during the earlier part of the 
stroke, because it is then that the ports are opening, respec- 
tively, as a steam and an exhaust-port. It is for this reason 
that the lead of the valve is usually made equal for each 
stroke, irrespective of unequal points of exhaust. 



24 

On referring to Fig. 6, it will be seen that, while the port* 
opened quickly, their closure occurred slowly, the desira- 
bility of this action being self-evident, when we remember 
that after the piston has traveled, say, half its stroke under 
the full steam chest pressure, it would take considerable port- 
closure to materially affect the pressure in the cylinder be- 
tween that point and the point of cut off, while ou the oth^\ 
hand the exhaust port hiving opened quickly, and remained 
full open during two-thirds of the stroke, the greater part of 
the steam has escaped, and it would require considerable port- 
closure to effect aDy back pressure. 



25 



LAP ON THE EXHAUST SIDE OF THE VALVE. 

When steam lap is employed to cut off the steam supply to 
the piston early in the stroke it opens the exhaust port earlier 
than is desirable, and to remedy this defect what is termed 
exhaust lap is sometimes added to the valve. The term ex- 
haust lap means the amount to which the exhaust edges of 
the valve covers the exhaust edge of the cylinder steam port 
when in the middle of its travel. Thus, in Fig. 9, the dis- 




DC BlA 



tance from A to B on the one side, and from C to B on the 
other side, is the exhaust lap. It is measured on one side only, 
so that from A to B and from C to B, measuring respectively 
f -inch, the valve would be said to have f-inch of exhaust lap. 



26 

The effect of exhaust lap is to enclose in the end of the 
cylinder a portion of the exhaust steam, thus compressing it 
and causing it to fill the clearance (that is the distance or space 
between the piston, when it is at the end of the stroke, 
and the cylinder cover) and the steam passage, at a pressure 
proportionate to the quantity of steam so enclosed, or, in other 
words, to the point of compression. The manner in which the 
exhaust lap performs this duty is by closing the exhaust-port 
before the piston has reached the end of the stroke. Thus, in 
Fig. 10, the valve is shown in the position in which it com- 




mences this operation, and since the valve and piston are 
traveling in the direction denoted by the respective arrows, it 
follows that whatever steam remains in the steam passage, A, 
and in that end of the cylinder will be compressed by the ad- 
vancing piston. This effect is sometimes termed the compres- 
sion, and at others the cushion, one of its results being to 
cushion the piston ; and in this respect, as well as in that of fill 
ing the clearance and the steam passage with steam at a pres- 



27 

sure by the time the piston has arrived at the end of the 
stroke, it serves the same purpose as the valve lead, and that 
without drawing any steam from the steam chest. 

A nother effect of exhaust lap is to retain the live steam longer 
in the cylinder, or, in other words, to prolong the point of re- 
lease. To offset these advantages, however, we have the serious 
disadvantage that it acts to diminish the exhaust area, and in 
view of this fact it becomes absolutely necessary, when ex- 
haust lap is employed, to vary some other of the valve ele- 
ments, in order to keep the exhaust free. In some cases the 
wid h of the cylinder exhaust-port is increased, in others the 
valve is given extreme travel as well. The introduction of 
these new elements creates so many considerations that it ren- 
ders it much more difficult to calculate clearly the results, and 
renders the calculations much more liable to error. It is for 
these reasons that so much difference is found in actual 
practice, with reference to the employment of exhaust lap 

In Fig. 11 is shown the valve from which the diagram in 




28 



Fig. 6 was taken, "there having been (in Fig. 11) 5-16ths of ex- 
haust lap added to it, and in Fig. 12 is shown a diagram of 
the valve movement under this new condition. From this 
diagram it will he observed that the exhaust is cramped early 
in the stroke, and (referring to the full line diagram) by add- 
ing up the total lengths of the vertical lines on the steam and 



Ncaro >» , 0>oNooC^s V. 







exhaust sides respectively, and then dividing their sum of the 
number of vertical lines (which will give us the average port 
openings) we shall find but a very little difference between the 
effective area of the port acting as a steam port and as an exhaust 
port, whereas the opening requires to be much greater for the 
exhaust than for the live steam, because, as the pressure of 



steam on the exhaust side is reduced, the exit of the steam 
remaining in the cylinder takes place slower, and hence, unless 
the piston movement is a very slow one, the exhaust lap will 
induce a back pressure on the exhaust side of the piston, 
which will far more than outweigh any advantage gained by 
the compression. 

The partial exhaust closure, which is shown in Fig. 12 to 
to have taken place early in the exhaust, is due to the width at 
A, in Fig. 11, between the edge of the bridge and the exhaust 
edge of the valve, becoming narrowed by reason of the ex- 
haust lap. 

If the valve were given an increase of travel, the exhaust 
area would be still further diminished unless the cylinder ex- 
haust-port were widened, in which event we have the cushion 
as the advantage, and a larger valve with increased travel as 
the cost. 

In a large proportion of American, and in almost all Eng- 
lish practice, exhaust lap is not employed, except it be from 
l-32d to 1-lGth-inch, or just sufficient to isolate the two steam 
ports from the valve exhaust port when the valve is in mid 
position. 




CLEARANCE. 

In Fig. 13 is shown a valve having what is termed clear- 
ance, which means the amount of opening between the edge 
of the cylinder port and the edge of valve exhaust-port when 
the valve is m the middle of its stroke, in which position it 
follows that there is open communication between both ends 
of the cylinder and the exhaust. The object sought by the 
employment of clearance is to free the exhaust, and its use 
is therefore mainly restricted to valves having but little steam 
lap, or having excessive travel, and upon fast running en- 
gines. 

Were we to give clearance to a valve having no steam lap. 
the result would be that when it opened to admit steam, the 
latter would pass clear through the same port to the valve 
exhaust-port, until such time as the valve had opened on the 
steam side, to an amount equal to that of the clearance on the 
valve, and it follows, therefore, that the clearance must always 
be less than the steam lap. 

In Fig. 14is shown the action of a valve having |-'nch steam 



31 



lap and 3-16th inch of clearance. The movement is shown 
for one stroke only, so as to keep the lines clear of one another. 




The full line represents the valve action with the clearance, and 
the dotted lines show how the exhaust would take place if the 
valve had no clearance. The valve, it will be noted, begins 
to open f-inch earlier and is opened full an inch earlier, re- 
maining so during 2£ inches more of piston stroke, than it 
would without the clearance. It also takes away the com- 
pression. 

If this valve was used upon an engine running very slowly, 
it is a fine point as to whether the clearance would in this 
ease, be desirable or not, but if the engine ran at an ordinary 



32 

speed there can be no question but that the clearance would 
be highly beneficial. 

It is evident that to give clearance to the valve whose 
movement is shown in Fig. 5, would be useless because the 
exhaust is in that case open f -inch by the time the piston 
arrives at the end of the stroke — is full open when the piston 
has traveled 1-1 6th inch of the return stroke and remains open 
during 22 inches of the exhaust stroke ; and the only effect of 
adding clearance would be to open the steam-port earlier as an 
exhaust-port, and thus permit the steam to escape too soon. 



YALVE TKAVEL. 

We have in all our previous examples given to the valve a 
travel equal to twice the width of steam -port added to twice 
the amount of steam lap, which accords more with English 
than with American practice, and we may, therefore, proceed 
to examine the effect of an increase of valve travel (which 
is common in American practice), first applying it to the valve 
shown in Fig. 6, whose elements we will leave the same as 
before, save that the travel is increased from 3| inches to 4 
inches, and in Fig. 15 is shown the action of the valve under 
this new condition. 

The effect of the alteration has been that whereas the ports, 
acting as steam ports, obtained their maximum opening at the 
seventh inch for one, and at the fifth inch for the other 
piston movement, they were opened under the increased 
travel at the 2d and 2f respective inches of piston movement. 
On the exhaust side, however, a partial reclosure of the valve 
has taken place early in the stroke, while the cushion has 
been reduced f inch for one stroke, and increased f inch for 
the other. 

The average exhaust opening has been reduced in conse- 
quence of the partial reclosure of the port, the area of ex- 



33 




fcaust opening becoming but very little greater than that for 
the live steam, and this, upon the general principle that the 
port opening for the exhaust requires to be considerably- 
greater, and that in the rules for obtaining the required port 
area this fact is recognized, does not appear to be any advan- 
tage, since we have niched from the exhaust to add to the 
steam-port opening. Our alteration of valve travel has, 
furthermore, reduced the expansion for one stroke, so that in- 
stead of lasting during 3 inches, it lasts during 2| inches of 
piston movement, while for the other stroke the alteration has 
been to decrease the amount of expansion from occurring 
during 4£ inches to 3^ inches of piston movement. 
The release, as the point at which the exhaust begins is 



34 



termed, has, under the increased travel, taken place about f 
inch later for one stroke, and \ inch later for the other stroke, 
and this under ordinary circumstances would be of decided 
advantage, but in view, in this case, of the diminished area of 
exhaust opening, it becomes of but little if any advantage. 



^p^/e 




In order to understand clearly the reason why the increase 
of valve travel has made so much difference to the valve 
nun ement, it becomes necessary to examine into the alteration 
which has been made in the position of the eccentric. Sup- 
pose then, that in Fig. 16, A represents the throw line of the 
eccentric, and B a line at a right angle to a line drawn from the 
center of the eccentric rod eye, C, to the center of the bore of the 
eccentric, then from A to B will represent the lead of the ec- 
centric, and it follows that, since the distance between A and 
B increases in proportion as the points at which they are 
measured is remote from the center of the eccentric bore, there- 
fore, the longer the throw of the eccentric the more is its lead' 
notwithstanding that the throw line of the eccentric remains at 
the same number of degrees of angle to the line, B, so that by 
increasing the throw of the eccentric, we have rendered it 
necessary to take off some of its angular advance or lead, as 
denoted in Fig. 16, in which the dotted line, D, represents the 



35 

position of the throw line of the eccentric when adjusted 
to suit the increase of travel. If now we bear in mind that 
the throw lines are shown in the position they would stand in 
when the piston was at the end of the stroke, we shall per- 
ceive as follows : — 

It is self-evident that when the throw line of the eccentric 
stands in the position of the right angle line B in Fig. 16, the 
eccentric will impart a quicker motion to the valve than it 
will at any subsequent part of its next half revolution in the 
direction of the arrow, and it follows that when the piston is 
at the end of the stroke, and the steam-port is open to the 
amount of the lead, the nearer the throw line of the eccentric 
stands to the right angle line, B, the quicker will be the 
movement of the valve while opening the steam-port. 

On referring to the dotted circle and line, E, in Fig. 16, 
which represent the position of the eccentric when the piston 
is at the other end of the stroke, it will be apparent that the 
same remarks hold good, hence, as we increase the valve 
travel, or, what is the same thing, the throw of the eccentric, 
we must decrease the amount of eccentric lead in order to 
have the same amount of valve lead, and this alteration causes 
the opening of the ports to take place more quickly. 

In order to remove the partial exhaust closure, shown in 
Fig. 15 to have occurred during the early part of the exhaust, 
we may adopt either of the following methods : — 

The closure occurred from a contraction of the width at A, 
in Fig. 11. The amount of the closure, we find by measuring 
it in Fig. 15, was 9-32d inch, by narrowing the bridges to 
that amount, and thus making the cylinder exhaust-port 
9-16th wider the partial closure would be removed. This, 
however, would leave the bridges 15-32d inch wide only, 
and would reduce their capability to resist the abrasion due to 
the friction of the valve face. Were this alteration made, 
4 



36 

however, the amount of contact between the valve face when 
the valve was at the end of its travel and the face of the bridge, 
would be | inch in width, which is sufficient to form a steam- 
tight joint. 

Another plan would be to make each bridge 9-32d inch 
wider ; in this case, however, a new valve made 9-16th inch 
wider in its exhaust-port would be required. This plan in- 
creases the wearing qualifications of the bridges. 

A third method would be to leave the bridges the original 
width (f inch) and to make the cylinder exhaust -port 9-16th 
inch wider, and to make the valve exhaust-port wider to the 
same amount. 

It is obvious that the plan first mentioned would be applic- 
able for altering existing ports, so as to save getting a new 
valve. 



37 



POINT OF CUT-OFF. 



If the elements of a slide valve motion be designed to cut 
off the steam supply to the piston at a point earlier in the 
stroke than when the piston has travelled about three-quarters 
of its stroke, the action of the valve will be very irregular for 
one piston stroke as compared to the other, and for this reason 
the slide valve is not employed upon engines requiring to have 
the steam supply cut off earlier than at most two-thirds of the 
stroke, unless, indeed, the engine have a link motion which 
serves to diminish the valve travel and thus make the point 
of cut-off earlier. 

In Fig. 17 there is illustrated the action of a valve having 
the following elements : — Width of steam ports, 1 in. ; width 
of bridges, | in. ; width of cylinder exhaust port, 2 in. ; steam 
lap, 1^ in. ; exhaust lap, l-64th in. ; travel, 4^ in. ; lead of 
valve, | in. ; piston stroke, 26 in. ; length of connecting rod, 
72 in. 

It will be noted that, whereas in all our previous examples 
the width of the bridges has been f inch, it is now made an 
inch. This has been done so that (the cylinder exhaust-port, 
being twice the width of the steam-port, and the valve travel 
equal to twice the width of steam-port added to twice tha 
amount of the lap) the valve shall move so as to open the ports 



88 




full as steam-ports, which would not be the case with nar- 
rower bridges. 

In Fig. 17 is represented the action of the above valve, and 
the first thing to attract our attention is that the exhaust has 
taken place when the piston had arrived at 21 1 inches for one 
stroke and at 22£ for the other, thus giving very early points 
of release. 

The expansion commenced for one stroke at the 1?| inch of 
piston stroke and lasted during 4| inches of the stroke, and 
for the other, at the 15^ inch, and lasted during 5| inches of 
the stroke, or, in other words, the point of cut-off occurred at 
nearly two-thirds of one stroke, and at nearly three-quarters 
of the other stroke. 



39 

Comparing the area of port opening of the exhaust with 
that of the steam, we find, referring to the stroke represented 
by the full lines, that the area of that port as an exhaust was 
a trifle greater than it was as a steam-port, whereas on the 
other stroke, as shown by the dotted lines, the area of the port 
opening was considerably greater than it was acting as a 
steam-port. The cushion also occurs during more than an 
inch more of one stroke than of the other. 

The travel of the valve we find has been just sufficient to 
open the steam-ports full, and any greater travel would pro- 
portionately diminish the exhaust area by increasing the partial 
closure at the cylinder exhaust-port shown in Fig. 17, 
on the full line diagram, to have taken place from nearly the 
first to the ninth inch of piston movement. 

To prolong the points of release the valve would require the 
addition of exhaust lap. Such addition, however, would di- 
minish the exhaust area and thus prove undesirable. It would 
also increase the cushion. Any clearance given to the valve 
exhaust-port would act to make the points of release earlier, 
whereas they occurred too early as it is. 

It is only left then to accommodate an increase of valve 
travel by increasing either the width of the bridges or the width 
of the cylinder exhaust-port, and since the adoption of either 
plan necessitates to an equal extent the widening of the valve, 
it matters little which plan is taken. The objection to enlarg- 
ing the valve is that its friction to its seat, and hence the 
power necessary to operate it is increased. It follows that by 
variations in the travel, width of bridges, width of cylinder 
exhaust-port, lap on steam and exhaust side, and clearance on 
the valve, an almost endless variety of valve movements may 
be designed, and are, in fact, found in practice; but while it is 
quite praticable to the engineering student to ascertain by 
calculation the action of any given value and ports, yet dry 
4* 



40 

figures do not impress the memory, especially when eacl\ 
individual movement possesses so many points to be remem- 
bered. By calling in the aid of the eye and showing the 
whole of the valve action in a diagram, the results of any 
given combination of elements are so much more easily 
grasped and retained that it becomes desirable to illustrate the 
action of the valves on various existing engines by the same 
kind of diagram as we have used in explaining the functions 
of the various valve elements. 




JK S ; 18. 



THE ROCK-SHAFT. 

If the eccentric rod connects to a rock-shaft, as shown in 
Fig. 18, the position of the eccentric requires to be altered, 
because the rock-shaft reverses the motion of the valve with 
relation to that of the eccentric; and furthermore, the latter 
will require a less amount of angular advance or lead, to 
maintain the same amount of valve lead, as we shall presently 
perceive. By introducing the rock-shaft we also reduce the 
length of the eccentric rod. 

In Fig. 19 are shown diagrams of a vaive movement having 
the same elements as those shown in Fig. 6, save that in this 
case a rock-shaft having arms 5^- inches long is introduced; 
the eccentric rod being shortened from 4 feet 10 inches (the 



41 



fength during our previous experiments) to 3 feet 5 inches 
long. 

Here it will be observed that, whereas in all our former 
diagrams the full line figure (representing the stroke during 
which the piston travels towards the crank) has shown the 
ports for both the steam and exhaust to open the slowest, 
the introduction of the rock-shaft has caused them to open 
the quickest during that piston stroke, and since the piston is 
travelling the fastest during the first half of this stroke, the 
steam port opening becomes more proportionate to the piston 
movement. 




Our diagram (Fig. 19) shows the ports acting as steam 
ports, to have opened three inches earlier for one, and one inch 



42 



(of piston movement) earlier for the other piston movement 
than was the case in Fig. 6, and the reason is as follows : — 

Suppose that in Fig. 20, A represents the center of a crank- 
shaft, and that the circle B represents the path of the center 
of the eccentric. Suppose also the engine to have no rock- 
shaft, the crank-pin being at 8, the "direction of rotation being 
as denoted by the arrow. If, then, the eccentric be given an 
angular advance of 30°, its throw-line will stand at E. 

Now suppose that P represents the steam edge of one steam 
port and B represents the steam edge of the other steam port, 
both being equidistant from the centre H of the ports, then 
the amount of valve lead due to the eccentric advance from 
G to E (30°) will be the distance between G and B (the 
length of the eccentric rod being from A to H, which meas- 
ures the same as line if or the line from E to (?). 

Fig. 20. 




Now suppose the engine to have a rockshaft, and the eccen- 
tric (moved to its required position) be given the same 30° of 
angular advance, as at J, then the amount of valve lead due 
to this angular advance is the distance from P to X, which is 
greater than that from G to B. Hence it follows that with a 
given amount of eccentric angular advance the amount of port 
lead will be greater in an engine having a rockshaft, or what is 
the same thing. For a given amount of valve lead less angular 
advance is required for the eccentric in the one position than 



43 

would be required were it in the other. Now the nearer the 
throw line of the eccentric stands to a line at a right angle to 
the crank, the faster the valve movement while the crank is 
at and near the dead centers, and hence the more rapid port 
openings. 

By turning the eccentric upon the shaft we have reversed 
the effect of the irregularity of valve travel (due to the angu- 
larity of the eccentric rod) so that when the angularity of 
the connecting rod is (starting from a dead center) accelerat- 
ing the piston movement, the angularity of the eccentric rod 
is also accelerating the valve movement. When, however, 
the piston starts from the end of the cylinder nearest to the 
crank, and the angularity of the connecting rod is retarding 
the piston movement, the angularity of the eccentric rod will 
he acting to accelerate the valve movement, and hence is is 
that in Fig. 19 the full line diagram assumes the chracteristics 
of the dotted ones in former examples, by opening both the 
earliest and the fullest 



44 



EXAMPLES OF VALVE MOVEMENTS, TAKEN FROM 
THE MOST RECENT LOCOMOTIVE PRACTICE. 

The following examples show the action of the various 
valves when under full travel, and, therefore, irrespective of 
the action of the link motions when employed to reduce the 
Valve travel so as to use the steam more expansively. 

Fig. 21 represents the action of a valve having the same 
elements as those upon an ordinary 16 X 24 inch cylinder 
American passenger locomotive, the elements being as fol- 
lows : Length of steam-ports, 15 in. ; width of steam-ports, 
1£ in. ; width of bridges, 1 in. ; width of cylinder exhaust 
port 2|- in. ; outside (or steam) lap, f in. ; inside (or exhaust) 
lap l-32d in. ; travel of valve 5f in. 

The full line diagram represents the stroke when the piston 
is traveling away from the crank, the engine running for- 
ward. 

In Fig. 22 is shown similar diagrams of an English engine, 
the design of James Cudworth, the ports, bridges, etc., being 
of the same dimensions as the above, the only point of differ 
ence being that the Cudworth engine has f inch of steam-lap, 
and the valve travel is 4^ inches only. 

The most prominent difference between these respective 



45 



diagrams are as follows : The English engine used the steam 
expansively during 1| inch more of one, and If inch of 
the other piston stroke, and has a much more free exhaust. 
Its point of release, however, took place an inch earlier in 
one, and 11-lGth inch earlier in the other stroke, per contra, 



v^^^^^&$gfr^S&33 







however, it cushioned on the exhaust f inch more for one 
stroke, and an inch more for the other stroke. In prolonging 
the point of release the Baldwin engine possesses an advan- 
tage that is of vastly more consequence than is the earlier ex- 
haust cushion, and the main other consideration is the exhaust 



46 

area Let us take the other two full line diagrams and compare 
them by adding the length of the lines and dividing the sum 
by the number of lines, which will give us the average 
respective port openings, and we shall find as follows : Aver- 
age width of steam-port opening of the Baldwin engine, from 






7" 



I 



A 



s 38ty22* 



K 



to 






\ 



1 



&^^^^^^^-\ 



the beginning of the stroke to the point of cut-off, 1.07 inch. 
Average exhaust opening of the Baldwin engine from the 
opening to the closure of exhaust 15-16th inch. 

Average width of steam-port opening of English engine 
from the beginning of stroke to the point of cut-off, 9-10th 



47 

inch. Average exhaust opening of English engine from be- 
ginning of exhaust to closure of same 1.12 inch. 

It must also be observed that the loss of exhaust area in the 
American engine commences from the 2.^- inch of the exhaust 
stroke and continues to the 16^ inch, and that, although in the 
English engine the port acting as a steam port commenced 
its closure 6 inches earlier and continued it during over 3 
inches more of the stroke, this is of little import, since the 
port being full open until the piston had traveled 9f inches ol 
the stroke, and the port area being proportioned, as is gener- 
ally presumed to be the case in view of its acting alternately 
as a steam and exhaust, and, therefore, larger than it would 
be required if it acted as a steam-port, only a slight variation 
in the reclosure is but of little moment, and the same remarks 
will apply to the slight difference in the opening of the port 
as a steam-port. Thus we then have, when the valve is 
given full stroke, (that is to say independently of cutting off 
earlier in the stroke by the employment the link motion) the 
broad issue of the advantage of prolonging the point of re- 
lease an inch at the cost of reducing the exhaust area as above 
noted, this issue being involved in the increase in the valve 
travel. 

In Fig. 23 we have a diagram of the port openings of an 
engine built for the Midland (English) Railroad, the dimen- 
sions being as follows : 

Steam-ports 1£ inches by 15 inches ; cylinder exhaust port 
3£ inches ; bridge between ports 1 inch ; steam lap 1 inch ; 
exhaust lap ; travel of valve 4^ inches ; lead | inch ; size 
of cylinder 17X24 inches ; .length of connecting rod 5 feet 
11 inches. In consequence of the shortness of the valve travel 
we find here that the ports do not open to their full width as 
steam ports, and as a result, while the average steam port 
opening is | inch> the average exhaust port opening is 1^ 
5 



45 




inches. The point of release is at the 22d for one and the 
23d inch for the other stroke ; while to partly offset this 
early release, the cushion amounts to about 1£ inches for 
one and two inches for the other stroke. Another result of 
the small valve travel is that the expansion takes place during 
4^ inches of one and 4 inches of the other stroke, which is 
during a large portion of the stroke when compared to valves 
having a maximun of travel. The admission of the steam is 
ilentical for the two strokes during the first five inches of the 



49 



piston movement. A peculiar feature of this valve is the 
width of the cylinder exhaust port, which might he narrowed 
one inch without affecting the diagram in the slightest par- 
ticular ; the size of the valve might then he reduced an inch, 
with a corresponding diminution in the power required to 
operate it. In the design of this valve freedom of exhaust has 
evidently been the main consideration. 

In Fig. 24, we have a diagram of the poit openings of a 
Rogers Locomotive Works (of Paterson, N. J.) 16X24 engine, 
the dimensions being as follows : 

Steam-ports 1^-XlS inches ; cylinder exhaust port 2^ in- 




K.^^^W V.WV 



50 

ches; bridge between cylinder ports 1£ inches; outside lap 
I inch; inside lap £ inch ; travel of valve 5 inches ; lead of 
valve £ inches ; length of rock shaft arm 9 inches ; length 
of connecting rod 6 feet 10£ inches. 

A notable feature in this diagram is the large exhaust area, 
notwithstanding the over travel of the valve, and also of there 
being £ inch of inside lap, and this is due to the extra width 
of the bridges between the cylinder ports. The average steam- 
port effective area is 1.01 inches, while the average effective 
area of exhaust port is 1.07 inches, the latter being greater 



if 



^v^iv 






Ki&cf.&;\ 



1^L_ 



1 \VIJ1'.Jill/ 


XI 


I j 




S\^^\^ 


No^' 



51 

than that shown in Fig. 21, notwithstanding that the ports 
are ^ inch narrower (the outside lap being the same in both 
cases). 

In Fig. 25 are shown the port openings of a 16X24 inch 
cylinder, the design of the Grant Locomotive Works (of 
Paterson, N. J.) the dimensions being as follows : 

Steam-ports 1^X14 inches ; cylinder exhaust port 2^ inches ; 
bridge between ports 1 inch ; outside lap | inch ; inside 
inch; travel of valve 5 inches; lead of valve -fa inch ; length 
of rocker arm 10£ inches ; length of connecting rod 7 feet 1 
inch. 

In this diagram the points of admission, release and cushion 
are unusually regular for one stroke as compared to the other. 
It will be seen that in all those valves having increase travel, 
the steam is used less expansively, but the point of cut off and 
release are very even, whereas in those valves having lesser 
travel the expansion is more variable, the points of release 
more variable, and the cushion greater. 

In Fig. 26 is shown the pert opening^ of an engine, the 
proportions of whose valve details represent the average for 
American freight locomotives, the elements being as fol- 
lows : 

Steam ports l|xl4 inches ; width of bridge between ports 
1 inch ; outside lap ^ inch ; inside lap f inch ; lead -^ inch ; 
valve travel 5 inches ; length of connecting rod 7 feet ; length 
of rocker arm 10 inches. 

The average steam-port opening is here shown to be 1.09 
inches, and the average exhaust opening is T 8 ^ inch. The 
reclosure of the exhaust port commences it will be observed, 
when the piston has moved but 1^ inch of the stroke, and 
while acting as a steam-port, the ports remained open during 
some 13 inches of the piston stroke ; when acting as exhaust 
ports they remained open during about 2£ inches of piston 
stroke. 



52 




K^^* V^V^S^N- ^sJv^U\i < <5> 



^^J^ OsjUy<sW\» 



In Fig. 27 is a diagram of the port openings of a representa- 
tive of the engines used upon the Susquehanna division of the 
Erie R. R, the proportions being as follows : 

Size of cylinders 18x24 inches ; width of steam ports 1 
inch ; length of steam ports 16 inches ; width of cylinder ex- 
haust port 2\ inches ; width of bridge between ports If inch ; 
outside lap || inch; inside lap -^ inch; travel of valve 5 inches; 



lead of valve y 1 ^ incli ; length of connecting rod 7 feet 2 
inches. 

In these proportions the extreme length as compared to the 
width of the steam-ports and the increased width of the bridge 
are notable features. The average opening of the steam-port 
is T 8 Q inch and that of the exhaust port is 1.05 inch. 



7W*V. 



v.V^V^^-^ 



^^^ 




We may now institute a comparison of the actual admission 
and exhaust area of the ports whose openings are illustrated 
in the various diagrams, for it will be noted that the average 
amount of openings so far given have referred to the width of 
opening irrespective of the lengths of the ports. 



54 

First, however, it may be pointed out that the element of 
time is an important consideration, for a given area of steam 
port which would be ample under a slow speed may be al- 
together inadequate under a much increased speed of engine. 
Indeed it is obvious that with sufficient time a comparatively 
very small port area will give ample admission and exhaust. 
As a practical illustration of this fact, we have the circum- 
stance that a great many locomotives will run faster with the 
links hooked up to shorten the valve travel, than with the 
valve under full travel. The reason of this is that with the 
valve in full travel the steam follows the piston during a 
greater portion of the stroke, and hence there is more steam 
to exhaust during the exhaust stroke, and there is not time, 
in such case, for the exhaust to be sufficiently free to avoid 
back pressure. That back pressure must in such cases exist 
is proven by the following considerations. The amount of the 
engine lead being a given quantity, it is obvious that with a 
free exhaust the further the live steam follows the piston the 
faster the engine should run, or to use other terms, if, with 
the live steam following the piston (say) two inches more of 
the stroke in one case than in another, and the engine speed 
is the same in both cases (the amount of the load remaining 
constant,) where are we to look for the duty due to the in- 
creased consumption of steam in the cylinder during those 
two inches of stroke, and for the increased pressure (due to 
the same two inches of live steam,) which exists during that 
part of the stroke in which the steam was working expansive- 
ly? The amount of power represented by that steam has been 
lost to the boiler and cannot be found in the duty except it be 
that the exhaust pressure is counted as duty. Possibly in 
many cases it may not be altogether lost for the following 
reasons : 

If the exhaust is cramped there may be left in the cylinder 
a large portion of the exhaust steam, which is compressed 



55 

and used with the live steam during the next stroke; suppos- 
ing this then to be the case, we have an engine large enough 
in all its parts to do a certain amount of duty, but from a 
contraction of exhaust area the engine can never be employed 
to perform that amount of duty save at being started. This 
exception indeed deserves particular attention as app'ied to 
locomotives, the reasoning being as follows : 

In starting, the speed being slow, there is time, with the 
valve in full travel, for the steam to exhaust without undue 
loss from back pressure, and when the train is under head- 
way the travel of the valve may be reduced by hooking up the 
link. Again, when ascending a grade sufficiently steep to 
reduce the engine speed, the valve may be given full travel. 
Thus full travel may only be used when the speed of the en 
gine being reduced there is given time for the steam to find a 
practically free exit. The considerations then resolve them- 
selves into this. Is it more desirable that the full power of 
an engine shall be capable of being exerted at starting, and 
under heavy duty due to steep grades, or during the average 
duty during the entire trip? and furthermore, what are the 
objections to giving to the cylinder an exhaust practically 
free at the greatest speed the engine may be called upon to 
run? If there are many steep grades and frequent stoppages, 
the first proposition will readily commend itself, unless the 
latter proves unattainable by reason of involving other and 
equivalent disadvantages. If, however, we carefully investi- 
gate the diagrams we shall scarcely find such to be the case, 
in many of them at least, fcr those diagrams in which no re- 
closure of the exhaust port has been shown to take place, 
and in which therefore the effective area of the ports, acting 
as exhaust ports, exceeds their effective areas when acting as 
steam-ports, will bear favorable comparison with those in 
which such is not the case. It is worthy of note also, that 
the reclosure of the exhaust port usually occurs from over 



5G 

valve travel or from exhaust lap ; when ever travel is lis 
cause the steam is used less expansively in the cylinder and 
at the same time the cushioning is less; on the other hand, how- 
ever, the points of admission and cut off are more nearly 
equal in the two strokes. When exhaust lap is the cause, 
the expansion an 1 the cushion are increased at the expense 
of the exhaust. 

Here however another consideration as applied to locomo- 
tives claims attention, inasmuch as if we consider the train 
speed, the size of the driving wheels makes a difference. 
Suppose for instance that an engine is traveling at 20 miles 
an hour, the driving wheels being 4 feet 6 inches in diameter, 
a greater number of piston strokes will be made in a given 
time than would be the case if the engine ran at the same 
speed, and the wheels were 5 feet 6 inches in diameter; hence, 
with the valve and port elements of the same proportions in 
both engines, the exhaust would, in the latter case, be more 
free, because it would have more time in which to take place. 



57 



THE RESULTS OP THE FOREGOING EXAMPLES 
COMPARED. 

The great difference in the action of a valve shown (by 
our diagrams of examples) to accompany apparently slight 
differences in the elements composing the valve mechanism, 
and the numerous ways in which variations may be made, 
render it difficult to compare the value of one valve move- 
ment with that of another, or with others, as the case 
may be. Hence it becomes necessary to so present a sum- 
mary of the data given by the diagrams, that the results of 
all the examples in any particular of their operation may 
be read without referring to the diagrams. This we may 
best accomplish by means of a series of tables, the result 
obtained from each table being given in its last column, 
hence to proceed. Let the first column in table number 1 re- 
present the number o? the diagram referred to ; the second 
column the size of the steam-ports ; the third the size of the 
cylinder, and the fourth the distance the live steam followed 
the piston, or point of cut off, and the fifth the cubical con- 
tents of the space in the cylinder which requires to be fiLed 
with live steam at each stroke. 



IS 







Table 1 






Fig. 


Size of Ports. 


Size of cyl. 


Toint of cut off. 


Cubic feet of 
live fcteam 




Inches. 


Inches. 


Inches. 










per stroke. 


21 


1^x15 


16x24 


22 


*2'56 


22 


1Xx15 


16x24 


19^ 


226 


23 


1^x15 


16x24 


18^ 


215 


24 


l T 3 F xT5 


16x24 


22 


2-56 


25 


V/xU 


16x24 


22 


2-56 


26 


l#xl4 


16x24 


22 


2 56 


27 


1 xl6 


18x24 


22 


3 26 



We may now compose another table as follows : The first 
column shall refer to the number of the diagram as before ; 
the second shall contain the average width of steam-port 
opening (as shown by the respective diagrams) ; the third 
shall contain the effective area of the steam-port (obtained by 
multiplying the average width of steam-port opening by the 
length of the port) ; the fourth shall contain" the volume of 
live steam required per piston stroke, and the fifth shall pre 
sent the proportion of the port area to the live steam volume. 
Thus we shall have the space requiring to be filled at each 
stroke with live steam, and the effective area each port affords 
through which to fill it, while the last column will afford 
means of comparing the values of the ports relative to the 
duty. 

Table 2. 

Sq. inches of 
port area per 
foot of live 



Fig. 



Average Width d 
steam-port opening. 
Inches. 



21 

22 
23 
24 
25 
26 
17 



1-07 
•9 
•75 

1-01 
1-01 
1-09 
1-05 



Effective steam- 
port area. 
Square, incbes. 

J16-05 
13-50 
1125 
15-15 
14-14 
15-26 
16 80 



Volume of live 

steam. 

Cubic feet. 



2-56 
2-26 
215 
2-56 
2-56 
2-56 
3.26 



steam. 

6 270 
5-973 
5-232 
5-918 
5-523 
5-960 
5-153 



*This column in obtained by multiplying the area of the cylinder by 
the point of cut off, ihe question of clearance being omitted for simplifica- 
tion. 

•("This column is the product of the second column in this table multi- 
plied by the length of port given in the second column of our previous 
table. 



59 



Here, then, we find that the greatest proportion of steam- 
port area as compared to the volume of steam to be admittted 
is given by the valve whose movement is shown in Fig. 21, 
while that shown in Fig. 22 is second, and Fig. 26 stands 
third, and this notwithstanding that average width, of port 
opening is less in numbers 21 and 22 than in number 26. 
The reason of this is that 21 and 26 have a maximum of width 
of steam-port opening, while number 22 has a shorter period 
of admission. In the English engines (Figs. 22 and 23) the 
points of cut off take place earlier, and the amount of expan- 
sion is greater, hence the effective steam- port area is large as 
compared to the volume of steam to be admitted. In the 
next table the first column remains the same ; the second 
column represents the number of inches of the piston stroke 
during which the steam was used expansively. The third 
column represents the proportion of the stroke during which 
the piston w T as propelled by the steam (the full length of the 
stroke being represented by 48), and tin fouith column gives 
the amount of piston movement during which the compression 
occurred. 

Table 3. 





Amount of expan- 






Amonnt of compres- 


Fig. 


sion in inches cf 


Steam followed piston. 


sion inches of 




stroke. 






stroke. 


21 


IX 


« 


of whole stroke. 


% 


£2 


3 


45 

4 8 


tt tt 


IX 


23 


W 


if 


a tt 


itf 


24 


in 


» 


tt il 


H 


25 


*H 


47 
48 


it it 


H 


26 


2 


47 
48- 


ti ft 


IX 


27 


ltt 


14 


if tt 


Va 



It remains now to examine the relative volumes of steam 
contained in the respective steam passages, which we may do as 
in Table number 4, in which however the length of the steam 



CO 

passage is obtained as follows : The question of clearance be- 
tween the piston and the cylinder cover (that is the space 
between the cylinder cover and the piston when the latter is 
at the end of the stroke) is left out, since by supposing all the 
engines to have the same amount of clearance, that item need 
not be considered. Now the length of all the piston strokes 
is 24 inches, and the half of this is 12 from this latter number 
we deduct the width of one bridge added to half the width of 
the cylinder exhaust port, and the remainder is given as the 
length of the steam passage. This assumes the distance of 
the steam chest face from the cylinder bore to be equal in all 
the engines, an assumption which enables us to keep our 
tables clear of complication by disregarding the trivial or ex- 
ceptional differences in this respect which may perhaps be 
found in practice 

The steam contained in the passage, however, gives out ex- 
pansive power from the point of cut off to the point of release, 
or m other words during the term of expansion, hence it be- 
comes necessary to credit each engine with that item, which 
is done in the column under the heading of "expansive 
part" of stroke. 

Table 4. 



Pig. 



Fort area 
Sq. inches z 

21 18-75 

22 18-75 

23 18-75 

24 17-80 

25 17-50 

26 17-50 

27 16 00 



Length of 

passage. 
Lineal ina. = 


Contents of 
passage. 
= Cubic ins. 


Expansive part of 

stroke. 

Lineal inch.es. 


9-75 


182-81 


IX 


9-75 


182-81 


3 


9-25 


173-43 


W 


9 50 


16910 


1* 


9-75 


170-62 


1H 


9-75 


172-62 


2 


9-50 


152-52 


Ifs 



From this we find that in number 21 less power is imparted 
to the piston by the live steam contained in the steam passages 



61 



than is the case in any other, while 23 stands first and 22 
next in order of superiority. To present the relative effective- 
ness of the ports in a more simple form we make a table as 
below, in which the second column contains the comparative 
value of the port area in proportion to the cubic feet of live 
steam to be discharged, taking the port having the greatest 
area as being 1. Then in the third column we may place 
the comparative value of the expansive force obtained from 
steam in the steam passages, the maximum (obtained by Fig. 
23) being taken as 1. 

Table 5. 

Comuarati^ 
Fig. 

21 
22 
23 
24 
25 
26 
27 

Turning now to the same ports acting as exhaust ports we 
find as follows : 



Comparative value of 
port arei per cubic 
foot of live steam. 


Comparative value 

obtained from steam 

in passages. 


1-00 


•35 


•95 


-70 


•82 


1-00 


•94 


-41 


•88 


-38 


•95 


•47 


•82 


•44 



Table 6. 



Pig. 

21 
22 
23 
24 
25 
26 
27 



Average w'dth of 
exhaust openings. 
Lineal inches. 

•937 
1-120 
1110 
1-070 

1-070 

•800 

1-050 



X 



Length of ports, 
inches. 


Average enectn 
exhaust area. 

Sq. inches 


15 = 


14-05 


15 


16-80 


15 


1650 


15 


16-05 


14 


15-98 


14 


11-20 


16 


16-80 



From the result obtained in the last column of the above 
table we may compose another as follows : 



62 
Table 7. 

Average effective Volume of ste^m to he Sq. inches of exhaust 
Fig. exhaust area. disci rged per siruke. area per cubic foot of 

Sq. inchos. Cub c feet. exhaust steam, 

21 14-05 -r- *2'665 = 5-27 

22 16-80 2-365 7-10 

23 16-50 2-250 733 

24 10-05 2-652 6-05 

25 15-98 2-658 6-01 

26 11-20 2-659 4-21 

27 16-80 3-348 5-01 

*The volume here given is the quantity of liv* cteam admitted by the 
port acting a* a steam port, or, in other words, the volume of live steam 
admitted to the cylinder and steam passage. 

Taking the exhaust area of Fig. 23 (which hears the largest 
proportion to its duty) as "being represented by 1, we shall 
have the following relative exhaust port values. 

Table 8. 

■p. Kelative value of exhauet 

£lg ' port to its duty. 

23 100 

22 -96 

24 -82 

25 -82 

21 72 

27 -68 

26 57 

Here then we find a very great disproportion to exist be- 
tween the exhaust port areas and the duty, and the number of 
piston strokes, or wheel revolutions, in a given time being 
taken as equal for all, it is self-evident that the ports having 
the highest rates are unnecessarily large, and therefore waste- 
ful of steam, or else those having the lowest, being too smaP 
in effective area, produce back pressure. 

If, however, in the case of a locomotive, the train speed 
instead of the revolutions were taken, the size of the driving 



63 

wheels and the speed at which the engine is designed to run. 
would require to he taken into account and would alter the 
result. It may be noted, however, that the committee ap- 
pointed by the Railroad Master Mechanics' Association, in a 
recent report upon the subject of the sizes of locomotive 
cylinder ports, preferred to take the revolutions as we have 
done in our considerations. It may also be noted that the 
ports of Figs. 22 and 23 are English and fast running engines, 
requiring therefore larger exhaust areas; on the other hand, 
however, the sizes of their driving wheels are larger. As 
applied to stationary engines our deductions cover the whole 
ground because the revolutions represent the engine speed. 

Another and important consideration with reference to 
these exhaust areas is as follows. When the exhaust area is 
diminished in consequence of the partial reclosure of the 
cylinder exhaust port, as shown in Figs. 21, 25 and 26, the 
question of time assumes a new importance, inasmuch as there 
may be a considerable back pressure during the early part of 
the exhaust stroke which cannot be compensated for by any 
amount of increased exhaust freedom during the latter part 
of that stroke. An examination of the diagrams will show 
the ports acting as exhaust ports to have closed, as shown in 
the table below. 

Table 9. 

Fi B »gan to close at Finally closed at 

° ' inches of stroke. inches of stroke. 

21 20/ 2 23^ 

22 18 2§i% 

23 U/ 2 ..... 22Ji 

24 20 23X 

25 20 23^ 

26 
27 
Hence the ports shown in Figs. 21, 25 and 26 remained 
6* 



04 

opened longer than those shown in Figs. 22 and 23, but the 
latter remained full open up to the point where the closure 
began, while the former had partly reclosed early in the 
stroke. To estimate, therefore, the ralative Values of the ex- 
haust we must take this fact into consideration, which may be 
done as follows : 

By taking the piston strokes as being equal in a given time 
we are enabled to form an estimate of the values of the re- 
spective ports and valve proportions in relation to their 
respective cylinders and duties ; and for this purpose we may 
assume the wheels to be of equal diameters. Now suppose that 
a point on the periphery of the respective driving wheels 
moves at the rate of the 4Sth part of a revolution in two 
seconds ; now the exhaust takes place during one half of a 
revolution of the driving wheel, hence we may reason as fol- 
lows : In Fig. 28 the half circle represents the half revolution 




during which the exhaust occurs, and the 24 divisions upon 
its circumference represent each the twenty fourth part of its 
half revolution. It will be apparent then that the time occu - 
pied by a point on the periphery of the driving wheel will be 



65 



one second, in which to travel from one division to the next, 
or, what is the same thing, three seconds to travel three divi- 
sions, and as it will be easier and more explicit to take three 
seconds than one, we will divide off* the half revolution into 
eight periods, each representing three seconds of time. Now 
it is apparent that while the driving wheel is traveling through 
either of these respective periods the piston will move through 
a distance equal to the distance contained in each of the 
several periods measured along the hoizontal line A, as de- 
noted by the respective figures and marks above that line. 
Now it will be noted that we have marked off the half circle 
into as many equal divisions as there are inches in the piston 
strokes, hence, while those on the half circle will represent 
equal periods of time for the' motion of the fly-wheel, those 
on the horizontal line will denote inches of piston movement 
during that time. We have only then to compare the average 
time and piston movement (which will be equal for all the 
engines) in each of the eight divisions with the average port 
areas shown in the diagrams for each division, and we shall 
have made a comparison of the effectiveness of the exhaust 
ports with the element of time taken into account. 
Table 10. 
* Average Exhaust Port areas during Periods. 





F&. 


Fig. 


Fie:. 


Fig. 


Fig. 


Fig. 


Fisr. 


Periods. 


21 


22 


23 


24 


25 


26 


27 




Inc !. 


laches. 


Inches. 


Inches. 


laches. 


Inches 


Inches 


1st 3 seconds 17 -8 


18-75 


18-75 


18-75 


17-50 


1512 


16 -00 


2d " 


126 


18-00 


18-75 


18-75 


1512 


9-94 


16-00 


3d " 


103 


18-60 


18-75 


18-75 


13-10 


8-68 


1600 


4th " 


10-3 


18-75 


18-75 


18-75 


14-56/ 


9-52 


1600 


5th " 


13-1 


18-75 


18-75 


18 '75 


16-52 


11-76 


16-00 


6th •« 


14-4 


18-75 


16-20 


18-75 


17-50 


16-80 


16-00 


7th " 


18-1 


10-80 


9-05 


15-60 


15*54 


12-74 


15 20 


8th " 


6-6 


1,80 


•18 


2-25 


2-80 


•21 


4 00 



*Th9 above average areas are obtained by multiplying the averag 9 
lengths of the three respective lines on the exhaust side of each diagram 
(representing the respective period) by the length of the steam-porU. 



66 



To carry the data contained in the above table a step far- 
ther we might take the respective areas for each period, and 
calculate the quantity of steam that would escape through 
during the period, and from that deduce the pressure on the 
exhaust side of the piston when the same had reached the 
part of the stroke represented by the end of each period ; this 
however is scarcely necessary to our purpose. 

It will be instructive however to deduce from the foregoing 
tables the relative areas of the ports acting as steam and as 
exhaust ports, and this we may do in the following manner. 
In table number 11, the second column contains the volume of 
live steam requiring to pass through the port to fill the cylinder 
(up to the point of cut off), and the steam passage. The 
third column contains the effective area of the port acting as 
a steam port, and the fourth column shows the ratio of effec- 
tive exhaust area to the effective steam area. 
Table 11. 





„j 












M 






o 








O 
P. 


a 


1« 


ea 








sa 


® 


|S 


2 








£ * 


• » 


M w 


a 








.2 £ • 


« • ® 


«, A 


~ 33 








■ <* IS 


2 eSJ3 


® ~* 


to £ 






Fig. 


m " O 


► op e» 

3 5 .3 


"S 2 


03 * 












@3 


• 3 








5 t 3 


• © o3 


ma 










* 3 

00 


2 ■ 

CO 

> 




o 3 

"8 








. p. 


1 


•* 


« 






23 


2-250 


11-25 


16 50 


1-47 






27 


3-348 


12-80 


16-80 


1-31 






22 


2 365 


13-50 


16-80 


1-24 






21 


2 665 


16-05 


14-05 


114 






25 


2 658 


14-14 


15 98 


113 






24 


2-652 


15 15 


16 05 


1-06 






26 


2-659 


15-26 


11-20 


•73 





*This volume is tie total requiring to be admitted and exhauoted. 



67 

Here then we find that whereas the exhaust area in Fig. 
23 is .47 greater than the admission area in Fig. 26, it is '27 
less, Again, while the exhaust area,in Fig. 24 is '06 larger 
than the admission, in Fig. 27, it is -31 greater, and the con- 
sideration naturally arises that if in Fig. 24 the exhaust is 
sufficiently free the admission is unnecessarily large, hence 
the valve travel might he reduced sufficiently to give no more 
than the requisite admission area, in which case the steam 
would he used mo r e expansively and the exhaust area would 
he increased while the valve would require less power 
to operate it. In this connection it may be noted that a com- 
mittee of the Railroad Master Mechanics have recommended 
an addition of steam lap over that usually given, in order to 
secure more expansion; now since a reduction of valve travel 
will operate in tne same direction, as well as effecting the 
above stated advantages, it appears in every way desirable. 
Supposing, however, that, as shown in Fig. 27, an exhaust '37 
larger than the admission area is necessary to avoid undue 
back pressure, then the valve travels of Figs. 21, 25 and 26 
may be reduced, increasing their exhaust areas, using the 
steam more expansively and reducing the power necessary 
to their operation, as well as the wear of the valve and seat 
faces. 

The wearing surfaces of the respective valves are given in 
table number 12, the valves being allowed to overlap the 
ports an inch at each end of the ports. The wearing surfaces 
of the seats are given, so far as concerns the bridges, between 
the cylinder ports only, because the width of seat face out- 
side of the steam-ports varies considerably in practice. The 
surface of the bridges, however, always wears faster than the 
surface outside the ports, and furthermore the bridge surface 
always wears hollow in its length, as well as hollow as denoted 
by a straight-edge placed across the cylinder face and at a 
right angle to the length of the port, 



C3 





Table 12. 


Sizes of valves. 


Area of valve. A; 


laches. 


Sq. inches. 


1% x 17 


1275 


7^x17 


1317 


10 xl7 


1700 


8% xl7 


150-8 


7^x16 


120 


7^x16 


1200 


8^x18 


145-2 



Area of bridges 


. Valve travel' 


Sq. inches. 


Inches. 


15 


5^ 


15 


±*A 


15 


4K 


15 


5 


14 


5 


14 


5 


16 


5 



Fig. 

21 

22 
23 
24 
25 
26 
27 



AREA OF STEAM PORTS, SHAPE OF STEAM 
PORTS, AND WIDTH OF BRIDGES. 

The author has thought it the best to give the rules for find- 
ing the area of steam ports as given by recognized authorities 
on that subject, and to supplement these with numerous ex- 
amples taken from general practice, and the reader will at 
once observe the wide variation existing between theory and 
practice on this subject. It will be noted that the practice of 
extensive locomotive builders has been selected, and it may be 
further remarked that in stationary steam engine practice the 
same variation exists. It is necessary to add, however, that 
in comparing the area of the steam port with that of the steam 
cylinder only, the piston speed is assumed to be equal in each 
case, whereas, if much discrepancy existed in the piston speed, 
and the smallest ports accompanied the slowest piston speed, 
their relative efficiency would be increased because of the in- 
crease of time during which the steam would flow through 
them for each piston stroke. 

The area of a steam port should bear a definite proportion 
to the quantity of steam required to pass through it in a given 
time, and the following are the rules given by the various 
authorities named. 

Mr. Bourne, in his Catechism of the Steam Engine, says, "In 
slow-working engines the common size of the cylinder pas- 



sages is one-twenty-flfth of the area of the cylinder, or one- 
fifth the diameter of the cylinder, which is the same thing. 
This proportion corresponds very nearly with one square inch 
per horse-power when the length of the cylinder is about 
equal to its diameter ; and one square inch of area per horse- 
power for the cylinder ports and eduction passages answers 
very well in the case of engines working at the ordinary pis- 
ton speed of 220 feet per minute." The same author also 
says, "The area of the ports of locomotive engines is usually 
so proportioned as to be from one-tenth to one-eighth the area 
of the cylinder, in some cases even as much as one-sixth, and 
in all high speed engines the ports should be very large and 
the valve should have a good deal of travel, so as to open the 
port very quickly." 

Dr. Zeuner, in his work on the slide valve, gives the fol- 
lowing : "To find the proper area of port for an engine of a 
given piston speed, multiply the area of the piston in square 
inches by the number opposite to the given piston speed on 
the table below. 

Speed of piston Number whereby to multi- 

in feet per minute. ply the area of the piston. 

100 0-02 

200 0-04 

300 0-06 

400 0-07 

500 0-09 

600 0-1 

700 012 

800 0-14 

900 0-15 

1000 0-17 

In "The Slide Valve Practically Considered, " by N. P. 
Burgh, is the following : "The author's extended experience 
in engines of all classes, embracing all the modern improve- 
ments by the best makers, enables him to give the following 
correct formula for the area of the opening or port caused by 
the valve for the supply steam : — 



70 

High, pressure engines = HP. x '6 to "5 square inches. In 
*" Link and Valve Motions," by Auchinchloss, it says, refer- 
ring to the area of steam ports : '* This dimension ranks next 
to cut-off in its controlling influence upon the proportions of 
the valve seat and face. It may justly be considered as a 
base from "which all the other dimensions are derived in con- 
formity with certain laws. Its value depends greatly upon 
the manner in which the port is employed, whether simply 
for admitting the steam to the cylinder, or for purposes both 
of admission and exit. In cases of admission it is evident 
that the pressure will be sustained at substantially a constant 
quantity by the flow of steam from the boiler. But in case of 
exit or exhaust, a limited quantity of steam, impelled by a 
constantly diminishing pressure, forces its way into the atmos- 
phere with less and less velocity. If, then, the engine is sup- 
plied with two steam and two exhaust passages, the ports will 
be correctly proportioned when the areas of the latter exceed 
those of the former by an amount indicated by careful experi- 
ment. When, however, one passage performs both duties, it 
should have an area suitable for the exhaust, and be opened 
only a limited amount for the admission of steam. Very ex- 
cellent results have been found to attend the employment of 
an area equal to 0*04 of that of the piston, and a steam pipe 
area of 0*025 of the same, when the speed of the piston does 
not exceed 200 feet per minute ; but widely different factors 
are demanded by higher speeds like those peculiar to locomo- 
tives. 

In the year 1846 MM. Gouin and Le Chatelier instituted 
a series of experiments for ascertaining the value of such 
terms. These were continued about six years later by Messrs. 
Clark, Gooch, and Bertera upon engines of British manufac- 
ture. The various results having been collated and analyzed 
by Mr. Clark, were finally presented to the public in his val- 
uable work on "Railway Locomotives." From this it ap- 



71 



pears that, "with a piston speed of 600 feet per minute, an area 
of 0*1 that of the piston was found to give practically a oerfect 
exhaust." 

The same author then gives the following table for inter- 
mediate speeds of piston "on the assumption that a higher 
speed is usually attended by increased pressure." 



Speed of piston. 


Port area. 


200 feet per 


minute. 


•04 area of 


piston. 


250 


" 


•047 


" 


n 


300 


" 


•055 


" 


n 


350 


*4 


•062 


<< 


tt 


400 


ft 


•07 


tt 


a 


450 


" 


•077 


1 1 


1 1 


500 


f. 


•085 


tt 


tt 


550 


•' 


•092 


1 1 


tt 


600 


tt 


•1 


tt 


tt 



In practice, however, the proportions vary considerably in 
some cases, because of peculiar requirements, and in others 
without any very apparent reason ; especially is this latter 
the case in the matter of locomotives, as the following table 
discloses: 



Name of Engine. 


Size of cyl- 
inder. 


Size of 
steam ports. 


Area of 
steam ports 




Inches. 


Inches. 


Inches. 


The Duke (English) 


18x26 


HX15 


— 22^ 


Baldwin Engine, 


18X24 


liXl6 


= 20 


Cudworth Engine (English) 


17X24 


1£X15 


m 


P. & R. Kailway, 


18X24 


HX15 


Dickson Mfg. Co. Engine, 


17X24 


1±X16 


20 


"Adirondack " B. & A.R.R. 


18X26 


i*xio 


m 


"Brown." B. & A. R.R. 


18X26 


Hxu 


15* 



73 

Here it will be seen that the two last named engines have 
the largest cylinders and the smallest port area. They are 
the freight engines which have lately been undergoing tests 
upon the Boston and Albany railroad. In this connection, 
however, it may be noted that the apparent difference is some- 
what modified by variations in the valve travel — the first en- 
gine named in the list having but 3| inches valve travel, 
while the two last named have 5 inches. 

"We next come to a consideration of the proportions desira- 
ble between the width and length of a port. Suppose, for ex- 
ample, its area is determined upon as 18| inches. It may be 
1X18| inches, ±iX16'66 inches, 1|X15 inches, or 1^x12-5 
inches ; the area and contents of the passages remaining the 
same. It is self-evident that the length of the port must bear 
some proportion to the diameter of the cylinder, though our 
table shows considerable latitude in this respect. A long and 
narrow port gives the advantage that when the piston is at 
the commencement of its stroke, and the valve has left the 
steam port, say £ inch open, the latter, if 18 inches long, 
would permit the steam to pass into the cylinder through an 
area of 18xi=4^ inches ; whereas with a 1^ Xl2^-inch port 
standing | inch open, there would be but an area of 12£ xH 
=3| inches, only of opening for the steam to pass through, so 
that the long and narroAv port would give a more ready sup- 
ply of steam to the piston during the earlier portion of the 
stroke, assisting the exhaust also, to a similar degree ; further- 
more, the stroke of the valve is reduced. On the other hand, 
however, the length of the valve is increased, and its width 
diminished, and it becomes a question as to whether the long, 
narrow, and short stroke valve will require more or less power 
to operate than will the other. Suppose, then, that the area 
of port required is 18 ? inches, and that we examine into the 
respective merits of a port 18f Xl inch, and one 12£ XH mcn - 
Allowing, in each case, the bridges to be an inch wide, the 



73 

cylinder exhaust port to be twice the width of the steam port, 
the valves covering the ports an inch at each end, the valve 
having (as in Fig. 1) no lap, and just sufficient travel to 
leave the steam ports full open. The sizes of the respective 
valves will be 20^x6 inches for the long port, and 14^x8 
inches for the short port ; the respective areas being 124^ 
inches for the first, and 116 inches for the last named. In 
considering the pressure with which these respectives valves 
are pressed to their seats, and hence the power required to op- 
erate them, we may disregard (for simplicity's sake) the coun- 
teracting pressure placed by the live and exhaust steam on the 
underneath side of the valve, since that part of the subject will 
be treated of in connection with valves having steam lap, be- 
cau e it then becomes a more important element. To pro- 
ceed then, we multiply these respective areas by the steam 
pressure under which they are supposed to operate (say 100 
lbs. ), we shall obtain the total force with which the valves 
are pressed to their seats. We may now, for the sake of illus- 
tration, presume that each 100 lbs. of pressure of the valve to 
its seat will require a force of 10 lbs. to move the valve, and 
we have as follows : — 

Total pressure Equivalent Force re- 

of valve to of quired to 

seat. friction, move valve. 

Lbs. Lbs. Lbs. 

For long port, 12450 --10 = 1245 

For short " 11600 -=-10 = 1160 3 3480 

Here then it appears that the valve for the long port will 
require about 44 per cent, of the power to move it that is re- 
quired by its opponent ; and since it has been shown to give 
the most ready supply of steam, it is in both respects the most 
desirable. There would, however, be more friction of the 
steam upon the sides of the passages, and probably a greater 
amount of condensation would take place. 

In this connection it may also be observed, that in the case 



Travel 
of 

valve. 


Power required 

to move valve 

one stroke. 


Inches. 

2 


Inch Lbs. 

2490 



74 

of the long port the steam passages would be longer to an 
amount equal to the difference in width between the two 
ports compared ; these, however, are minor elements, espe- 
cially the latter, providing that the cut-off takes place early 
in the stroke, in which event the steam in the passage per- 
forms expansive duty after the cut-offtakes place. 

WIDTH OF BRIDGES. 

We next come to a consideration of the width of the bridges 
between the cylinder steam and exhaust ports (shown in Fig. 
1, at D D). The proper width of the bridge is often given as 
the same in amount as the thickness of the cylinder ; there is 
no reason, however, why this width should not be propor- 
tioned to its duty. It has first to separate the steam port from 
the exhaust port, and must therefore be strong enough to 
withstand the highest pressure (with the usual margin of ex- 
tra strength) to which the cylinder is intended to be subjec- 
ted. Here, however, it may be noted that the thickness of 
the bridge need not be uniform, but may be cut away at and 
near the face of the seat, thus obtaining a strong bridge with 
a narrow seat face. It must be remembered that a saving of 
a quarter of an inch in the width of the bridge, makes half 
an inch less in the required width of the valve, and by reduc- 
ing its area, operates (in the same manner as the narrow 
port) to diminish the amount of power necessary to operate 
the valve. 

It has, secondly, to maintain a steam-tight joint (with the 
valve) between the cylinder steam and exhaust ports. To 
form such a joint, a quarter of an inch is sufficient, so that if, 
at the extreme ends of the valve travel, there is left that 
width of contact between the valve and seat faces, a tight 
joint may be assured ; but whether so narrow a bridge as this 
would give will stand the wear so as to maintain a tight joint, 
is another question, and one depending upon several ele- 



75 

ments. If the valve travel is greater than that necessary to 
permit to the port a full opening, or in other words, if that 
travel is greater in amount than twice the width of the steam 
port in a valve (suck as shown in Fig. 1), or twice the width 
of the steam port, added to twice the amount of any steam 
lap that valve may have added to it, then the bridge has more 
duty placed upon it, in consequence of the necessary addition 
to the travel, and it should therefore have an addition of area 
to withstand the resulting additional wear. 

The hardness of the metal of which the seat is composed, 
and the pressure of steam under which the valve is required 
to operate, are also elements which go to determine the wear- 
ing qualifications of the bridge. It is evident, however, that 
(presuming the iron to be as hard as it can conveniently be 
operated upon by the machine cutting-tools) the area of the 
bridge should bear a definite proportion to the pressure of the 
valve to its seat, and the amount of the valve travel, or in 
other words, it should bear a definite relation to its duty ; the 
proportion of that relation being determined by results taken 
from actual experiment. 

The width of bridge is generally less than the width of 
the steam port, varying in English locomotive practice from 
about one and three-eighths to one and a quarter, and in 
American from fifteen sixteenths to one and a quarter inch, 
and the bridges are found in both cases to usually wear hoi 
low in their lengths. 
7* 



76 



THE POWER REQUIRED TO OPERATE A SLIDE 
YALVE. 

Any mathematical rule whereby to calculate the power re- 
quired to operate a slide valve is vitiated by the following 
facts : The rule must be based upon the unbalanced area of 
the valve, the force or weight pressing the valve to its seat, 
and the distance the valve moves through in a given time. 
The first and last of these elements may be very easily deter- 
mined, but the force pressing the valve to its seat is a quantity 
which varies with the shape of the valve, its size, strength, 
and the temperature under which it operates, or, in other 
words, it varies with the fit of the valve to its seat, and that 
fit is in a continuous state of change. 

When a valve is lying upon its seat in the open air, there 
should be, if it is fitted to its seat, the atmospheric pressure 
of say 15 lbs. per square inch of unbalanced area pressing it 
to its seat. The unbalanced area will be composed of the 
area of valve face in contact with the iron surface of the steam 
chest face or valve seat face, and will amount, in a small valve, 
to, say 25 inches, which, multiplied by the atmospheric press- 
ure, say 15 lbs., would give §75 lbs. in addition to the weight 
of the valve as the power necessary to lift the valve from its 
seat. As a practical fact, however, it does not matter how 
perfectly any valve, when new, may fit to its seat ; one month's 
wear will so entirely destroy the truth of the surfaces, that it 
may be lifted from its seat against the atmospheric pressure 
without the employment of 1 lb. per square inch more than 
that due to the weight of the valve ; indeed, it is not found in 
practice to require anything more than the simple weight of 
the valve. 

There can be but one explanation of this well-known prac- 
tical fact, which is, that the valve does not fit sufficiently 



77 

closely to its scat to exclude a thin film of air which acts to 
counterbalance the pressure on the back of the valve. 

That such a film of air may exist without affecting the prac- 
tical tightness of the valve is capable of indisputable demon- 
stration. Thus, take two truly surfaced plates, and, after 
carefully cleaning them, lower one vertically upon the other, 
and it will be found to float upon the other, gliding about with 
extraordinary ease. Then lift the top plate, and it will suspend 
the bottom one from the partial vacuum between the two sur- 
faces. 

CONDITIONS UNDER WHICH A SLIDE VALVE 
OPERATES. 

The conditions under which a slide valve operates while 
actually at work are widely different from those existing when 
it is at rest. First, as the boiler pressure fluctuates the tem- 
perature of the valve varies, causing the valve to expand or 
contract as the temperature increases or falls, and the irregu- 
lar shape of the valve prevents the valve face from expanding 
or contracting in a straight line ; hence the plane of its face is 
in a state of change constant with variations in the boiler 
pressure, and hence there is every probability, indeed, it ap- 
pears a certainty, that there is at all times a film of steam 
beneath a part of the valve face acting to offset the pressure 
on the back of the valve. During an extensive experience in 
repairing locomotives, I never yet found an old valve a suffi- 
ciently good fit to its seat to have any of the atmospheric 
pressure holding it to its seat, and if air finds its way beneath 
why will not steam also ? 

Suppose that all slide valves were made of an equally good 
fit to their seats (and this is supposing a good deal, when we 
remember that some engine builders put in the valves just as 
they were planed, making no attempt to fit thorn to their 
seats on the cylinder port faces, while other3 file them to a fit, 



and others again scrape both valve and seat true to a surface 
plate). Suppose that the co-efficient of friction, whether due 
to the pressure only of the valve to its seat or to the combined 
pressure and induced adhesion from perfect contact, was in 
all cases alike, when the valves were put in new. 

Let us see how long they would remain so. First, then, 
an iron or brass casting, heated after having the surface re- 
moved by planing or filing warps, and its fit is impaired. 
With the loss of the fit goes a loss of the adhesion, and an 
admission of steam beneath that part of the valve which does 
not fit. How much it will warp depends upon the tempera- 
ture to which it is heated, on how much was cut off the planed 
face, on how unevenly the valve casting cooled after being 
taken out of the mould, on the shape and thickness of the 
valve, and on several other elements. Let us presume, how- 
ever, that a casting could be made so that it would not warp 
from having its surface skin removed, and that, by heating 
the valve after it had been once surfaced, the reset had taken 
place, and the valve, being refaced true, would not again 
warp from being reheated (as experience demonstrates that it 
always does), and that, being heated to a given temperature, 
it would remain as close a fit to its seat as it was when cold. 
Then, just so soon as the temperature varied, the expansion 
and shape of the valve would vary. Cast iron expands by 
heat, in proportion to the temperature. The valve has, acting 
on the inside area of its exhaust port, the cooling effects of 
the atmosphere, which finds ingress through the exhaust 
pipe. The exhaust steam itself lowers in temperature as its 
pressure decreases, and the live steam on the back of the valve 
is comparatively constant in temperature : as a result, then, 
the valve is continually changing in form from the expansion 
due to the high temperature of the exhaust steam during the 
early part, and the lower temperature during the latter part, 
of the exhaust. Kow com.s another and more important 



79 



question, and that is : How far will the spring of the valve, 
from the pressure of the steam upon its back, affect the "fit to 
its seat, and will it so spring as to permit of a fine film of 
steam finding its way beneath the wings of the valve, thus 
relieving, to a certain extent, the amount of its pressure to its 
seat? 

If we take a pair of the plates shown in Fig. 29, and get 



Jfy-Zf. 




them so closely together that it requires, say, 340 lbs. to slide 
one upon the other, and then take hold of the plates by the 
handles, as shown in our engraving, we can pull them apart 
by exerting a force of about 130 lbs. ; in other words, it will 
require but little more than one third as much power to pull 
them apart, in this manner, as it requires to slide one upon 
the other. In thus pulling them apart, we have, upon the 
back, whatever weight of the atmosphere the fineness of the 
fit leaves unbalanced, and, in addition, whatever amount of 
adhesion the perfect contact of the surfaces may induce. 
Hence, allowing a co-efficient of friction of - 15, we should 
have 2,27G lbs. holding the plates to gether ; and while allow 



80 



ing a co-efficient of 23-7, we should have 1,440 lbs. resisting 
the effort to pull the plates apart. The fact, therefore, that 130 
lbs. will actually, under the conditions shown, pull the plates 
apart, appears at first sight not a little singular. The solution, 
however, is simple enough. The plates spring from the press 
ure placed by the hands upon them, and hence they unlap and 
come apart just as if we took two sheets of paper, placed to- 
gether and soaked with water, and then took hold of two 
corresponding corners and pulled them apart. The plates are 
£ inch thick in the body, and the ribs are each T 7 F inch 
thick and 2§ inches high ; and yet 130 lbs. applied as shown 
will spring them sufficiently to let the air get in between 
them. Let us in the light of this fact examine the shape and 
pressure upon a slide valve (assuming for the nonce that the 
pressure is the unbalanced area in contact multiplied by the 
steam pressure), and ascertain whether it is reasonable to sup- 
pose that the pressure of the steam upon the valve spring 
the wings, and permits the steam to find its way beneath 
them. 
In Fig. 30 is shown an ordinary locomotive slide valve, the 




ports being 1| x 17 inches, the bridges between ports 1 inch 
wide, the cylinder exhaust port 2^ inches wide, and the 



81 

valve having 1 inch of steam lap, eovering the ends of the 
cylinder ports 1 inch at each end. When the valve is in the 
position shown, it will be noted that there is a very large 
proportion of the area of the valve unsupported by the seat ; 
the area of this portion will be in this case 5| inches, as 
marked in the engraving, one way, and 17 inches the other 
= 97 75 inches. Now supposing the steam pressure to be 130. 
lbs. per inch: then 97'75 X 130 = 12,707 lbs., the assumed 
pressure of the valve to its seat, tending to spring the flanges 
or wings in the direction denoted by the dotted lines, E and 
F, respectively. What have we to offset this amount ? The 
area of one bridge equals 17, the area covered under the valve 
flange at D equals 11 inches, and the amount of the valve 
flange overlapping the ends of the steam ports equals 15*5 ; 
total 43 - 5 square inches, which, multiplied by the steam pres- 
sure, would give 5,855 lbs. as the pressure tending to keep 
the valve wings from springing. There will, it is true, be a 
pressure placed on the underneath side of the valve by the 
exhausting steam, the area thus acted on being, in the position 
shown, 97*79 square inches ; but it can scarcely be advanced 
that this pressure can be sufficient to relieve the valve from 
its liability to spring from the 6,852 lbs.»on the other side. 

Theoretically, a valve will spring of its own weight ; and 
that it will spring from the pressure which a man can put 
upon it with his hands, I have often found in facing valves 
up. For example, if, in trying the valve on the surface plate, 
the former is pressed in the middle by the hands to make the 
plate mark the face plainly, and the valve is fitted under 
these conditions to a practically perfect fit, the surface plate 
marks showing equally all over, we may then let the valve 
lie upon the plate of its own weight only, and the marks will 
show (after of course moving the valve back and forth) at 
and near the edges of the valve only, showing that the pres- 
sure of the hands sprung it. There are plenty of instances of 



82 

metal in the most solid of forms springing of its own weight : 
witness the Morton Poole rolls, which, though of chilled cast 
*ron and 12 inches in diameter, spring and bend by the inser- 
tion between them of a piece of gold leaf ■g^f inch thick. 
There is yet another part of this question, however, which 
is found in practice to be of the utmost importance, and that 
is (as a visit to any locomotive repair shop will demonstrate, 
by the engines that come in to be repaired), that the valve 
wears out of truth, and so does the seat. In my experience, 
I have chipped a full T ^ inch off valve seat faces without cut- 
ting the worn grooves out. I have examined, or had come 
under my observation, at least 400 slide valves, and I never 
saw one that was, after working three months, of a sufficient 
fit to its seat to require one pound more than its own 
weight to lift it from its seat ; whereas, if such a valve as is 
shown in Fig. 30 were of a practically perfect fit, it would 
require, when in mid-position, some 800 lbs. to lift it vertically, 
taking hold of the ribs outside the arch. The fact is that the 
bridges wear hollow lengthways, and hollow, as denoted by 
a straight edge, over the seat and across the bridges. Then 
there usually wears in the seat face a groove at right angles 
to, and close to, the edges of the ports. To remedy this, a 
practice sprung up in England, in about the year 1865, of 
drilling, in the face of the valve and in a line with the ex- 
haust-port edge, a hole in each wing ; and this hole may be 
found mentioned in recent English engine specifications. 
Now just so soon as a valve face loses its smoothness, though 
the grooves may be only the one hundredth of an inch deep, 
or like coarse file marks, it becomes impracticable to exclude 
the surrounding air at atmospheric pressure, let alone steam 
at a high pressure, from between the surfaces. 

I have a plate of the same size as those shown in Fig. 29, 
which has been planed and not fitted in any way. The 






63 

planer marks are all intact. By placing a finished true plate 
upon it, the partial vacuum between the two will lift the 
planed one ; but in about ten seconds it will fall, because the 
weight of the plate causes it to sag, and the air travels along 
the fine planer marks until there is not sufficient vacuum to 
sustain the weight of the plate, which is about 20 lbs. Now 
since the planed plate can be lifted by the vacuum, it is at 
least as good a fit as an ordinary slide valve, and' under a 
steam pressure would undoubtedly be steam-tight, although 
the steam, like the air, would find its way along the planer 
marks, and thus counterbalance a large proportion of the 
pressure placed by the steam on the back of the valve. How 
much the elements of warping from expansion, changing 
form from irregular temperature, and counterbalancing from 
steam finding its way beneath the valve, will affect the press- 
ure of a valve to its seat whether these causes act either in 
concert or partly counteract each the other, will depend upon 
the shape, size, strength, etc., of the valve. 
8 



84 



COEFFICIENT OF FRICTION. 

If we attempt to ascertain the power required to operate a 
slide valve by any of the rules given by various authors, we 
are at once confronted with several difficulties. First, we 
have no data as to how the friction of metal surfaces is affected 
by the metal being heated to various temperatures. Secondly, 
the dryness or wetness of the steam must have an important 
bearing, since steam acts to a certain extent as a lubricator, 
and the degree of that extent varies according to its saturation 
or wetness as it may be termed. Thirdly, we have no data 
which enables us to determine whether the closeness of the fit 
of the valve to its seat in those parts of its area which have no 
interposed film of steam beneath induces any adhesion of the 
surfaces which some experimenters claim exists in addition to 
the friction due to the pressure forcing the surfaces together. 
Since, however, this part of the subject will be referred to 
presently, we may now place before the reader the generally 
accepted table of coefficients of friction. 

The experiments of General Morin on the friction of vari- 
ous bodies without an interposed film of lubricating liquid, 
but with the surfaces wiped clean by a greasy cloth, have 
been summarized by Professor Rankine in the following 
table. 



83 

Friction in terms cj 
Angle of repos«. the weight. 

Metals on metals, dry $p to ll^o 015 to 02 

Metals on metals, wet 16^° 03 

Smooth surfaces, greased 4° to 4J° 0'07to0*08 

Smooth surfaces, best results lfoto 2° 03 to 0*36 

In a paper, of which an abstract has appeared in the Comp- 
ies Rendus of the French Academy of Sciences, for April 26, 
1858, M. H. Bochet describes a series of experiments which 
have led him to the conclusion that the friction between a 
pair of surfaces of iron is not, as it has hitherto been believed, 
absolutely independent of the velocity of sliding, but that it 
diminishes slowly as that velocity increases. 

If we class the conditions under which a slide valve operates 
under the head of "metals on metals, dry," we are confronted 
at once with the question : For what reason shall we select 
the co-efficient as 15 in preference to the 0*2, or vice versa? 
If we class those conditions under any other of the headings 
in the table, where are we to get a co-efficient of 15 ? And 
if, as M. H. Bochet concludes, the co efficient varies with the 
velocity of sliding, how can we assume a fixed co efficient for 
a slide valve when its velocity of sliding varies with every 
variation in the speed of the engine, as well as at every inch 
of its movement ? In the case of slide valves, however, the 
weight upon the valve is not a dead weight, but live steam 
which will find its way beneath the surfaces and remain 
there. 

In Appleton's "Cyclopaedia occurs the following : "Two 
glass or metal plates with well ground surfaces, when pressed 
together, will adhere with such force that the upper one will 
not only support the lower, but an additional weight will be 
required to separate them. The amount of this adhesive 
force has been measured by recording the weights necessary 
for their separation. The records of the old experimenters on 



86 

this subject are worthless, because they placed a lubricating 
fluid (oil or fat) between the plates ; they found thus the 
cohesion of the oil or fat, and not the adhesicn of the plates. 
In later times, Prechtl, in Germany, has made the most care- 
ful experiments in this line ; he took polished metal plates of 
1£ inch diameter, suspended the upper one to a balance, 
brought it to an equilibrium in a horizontal position, and 
attached the lower plate to a support beneath it. Both plates 
were then brought into contact, so that the flat polished sur 
faces covered one another perfectly, and the weights required 
in the scale, at the other end of the balance beam, to separate 
the plates were the measures of adhesion. He found thus the 
following remarkable law : The adhesion between two plates 
of the same material is the same as that between one of the 
plates and any material which possesses a less adhesive foice. 
Prechtl found also that an attraction of the plates manifested 
itself at an appreciable distance before actual contact, and he 
even measured the amount of this attraction at the distance 
of Jj of an inch by means of weights in fractions of grains. 
The suspended plate, when brought within this distance, was 
attracted with an accelerated motion till the contact took- 
place with a slight concussion. The idea that the pressure of 
the air was the chief cause of the adhesion of two such plates, 
as it is in the case of the well known experiment with th3 
Madgeburg hemispheres, was set at rest by Boyle, who sus- 
pended the adhesive plates charged with weight m the 
vacuum of and air pump ; the plates were not separated, while 
the hemispheres held together by the vacuum alone feliaDart. 1 ^ 
In cast iron the amount of oil that will remain in the pores 
of the metal, even after careful wiping of the surface with dry 
rags, is sufficient to affect the friction of the surfaces, so that 
after such a surface has been oiled it is necessary to use alco- 
hol in order to thoroughly remove the oil. 



"87 

A practical experiment made by me upon a pair of cast-iron 
surface plates weighing 23 lbs. each and having an area of 96 
inches demonstrated the following : With the top plate low- 
ered vertically upon the bottom, it did not require an ounce 
to move the top plate, both plates being dry, but if there was 
one drop or one-quarter of a drop of oil distributed over the 
192 inches of area of the two plates, it wOuld require 50 to 100 
lbs. to slide it, according to the amount of lubrication. This 
will always be the effect of slight lubrication upon closely fit- 
ting smooth surfaces, since the oil acted to exclude the film of 
air that would otherwise remain between the faces. Freely 
lubricated, the plate would require about 5 lbs. to slide it. 
If, however, the surfaces are wiped clean with oil and rag 
and are then wiped dry with the rag, and if we then place the 
plates in contact at one corner only, and slide the top one over 
the other, it has taken 341^ lbs. to slide one over the other, as 
appears from a test made by Messrs. Fairbanks upon their 
standard scales at the Centennial. 

Now the area of the plate 96 inches multiplied by the atmos- 
pheric pressure per square inch 147 = 1411*2, add the weight 
of the plate 23 lbs. and we have a total of 1434 2 lbs. pressing 
the plates together. Now since the power required to slide the 
plate expressed in hundreds is 3*415, we divide that amount 
into the total 14346, and obtain 23 as the power required to 
slide the top plate for every 100 lbs. pressing it to the bottom 
one, or, in other words, we obtain a coefficient of friction of 
•23. This is higher than that given by Morin for cast iron or 
cast iron dry (as the plates were), and this could only arise 
from the surfaces being in more perfect contact or from the 
adhesion referred to. If in an experiment to determine the 
coefficienfcof friction the simple weight of the sliding piece is 
taken, it becomes an open question whether the surfaces ex- 
clude the air sufficiently to cause the atmospheric pressure to 
exert any influence whatever upon the external area, and if, 
8* 



88 

on the other hand, the atmospheric pressure is taken in addi- 
tion to tlie weight of the piece, it hecomes a question how 
closely the surfaces fit together. 

The size of the valve is a very important element, since it is 
obvious that in the case of a very large valve, such as is some- 
times used in marine engine practice, it would be impracticable 
to make it strong enough to resist local distortion, causing it 
when under pressure to warp and fit more closely to its seat 
in those parts of the surface where the valve face, when not 
under pressure, would not fit to the seat. 

It would take an enormous pressure to warp a block of cast 
iron 3 inches square and 2 inches thick sufficiently to destroy 
its close fit when the pressure was exerted all over its exposed 
area, even though it were supported, as on the bridges of a 
steam chest face, but were the piece 18 inches square a mode- 
rate pressure would make a sensible alteration ; while a va- 
riation of 100° of temperature would affect even the small 
block to a sensible degree. 

THE LUBRICATION OF SLIDE YALYES. 
In many cases the lubrication of a slide valve, though neces- 
sary to prevent the surface from rapid abrasion, may act to in- 
crease the power necessary to operate the valve, unless, indeed, 
it be both copious and constant in supply. It has been stated 
that a fine film of oil acted to exclude the film of air from 
between the surfaces that were made by me as experiments 
on the surface plates before referred to, increasing the power 
required to move the top plate from 1 oz. up to 100 lbs., and 
this I have found in many experiments always to be the ease, 
the effect increasing with the smoothness and truth of 'the surfaces. 
Furthermore, on a very smooth surface, and at the same time 
an imporous surface, the oil is rapidly wiped off by the mo- 
tion, whereas, on one that appears bright and smooth to the 
eye but pitted when put under a magnifying glass of ordinary 



89 

power, the effects of slight lubrication remain longer, probably 
because the oil remains longer in the minute depressions. 

Now, with the continuous change of form shown in previ- 
ous remarks to accompany the operation of a slide valve, the 
surfaces cannot remain in close contact, and the oil remains 
to some extent between tbose parts of the surfaces least in con- 
tact, hence lubrication undoubtedly assists the easy operation 
of the valve. 

PRACTICAL METHOD OF FINDING THE WORKING 
RESULTS OF A GIVEN SLIDE VALVE. 

A simple method of ascertaining, with a pair of compasses 
and a square, the working results of any given slide valve is 
shown in Fig. 31. 

Suppose the given proportions of the valve are as follows: — 

Inches. 

Width of steam ports f 

Width of cylinder exhaust port 1 \ 

Steam lap on valve | 

Travel of valve 2f 

Stroke of piston 24 

Draw the circle J., its circumference representing the path of 
the crank-pin and its diameter representing the piston stroke, 
but since to draw it full size would be inconveniently large, we 
may draw it to a scale of £ inch per foot. Draw the circle B, 
whose diameter must equal the full stroke of the valve (in this 
case 2f inches), both circles being struck from the same cen- 
tre. Now draw the vertical line (7, which must pass through 
the centre of the circles. To the right of 6 T , and at a distance 
from it equal to the lap of the valve, draw the line D. 

Draw the small circle 1, which represents the crank-pin (on 
its dead-centre furthest from the engine-cylinder) ready to 



90 

begin its stroke. Place one point of a pair of compasses on 
the centre of circle 1, and the other point (at the intersection 

Fig. 31. 



k- 






j-f ° 



/ STEAM, H (M 



AS AN 

EXHAUST 

PORT. 



£4 ft 



91 

of D with the circle B) on B at E. Now, since one point of 
these compasses will always be applied to A, and the other to 
B, we may term them respectively the A and the B points. 

The line D now represents two things : first the edge of the 
valve, the eccentric being set forward or advanced on the 
shaft sufficiently to take up the lap of the valve S, represent- 
ing that angular advance, as it is termed (its amount being 
its angle from the line C). 

We have now marked the relative positions of the crank- 
pin (at 1) on its dead centre and the position of the edge of 
the valve (at E), and, since the eccentric is fast to the crank- 
shaft, it is evident that their distances apart will remain the 
same at every point in the crank pin revolution. 

Now mark the line F, whose length must equal, from the 
line B to its point of junction with the circle 2?, the width of 
the steam port, in this case finch, F being at a right angle 
to D. 

Now while the eccentric moves in the arc of a circle from 
Eto G, the edge of the valve moves in a line from B to (?, 
and as F is the width of the port, the latter will be full open 
when it arrives at G. If, then, we place the B point of the 
compasses at G, and with the other point mark a point on the 
circle A, this point will denote the position of the crank-pin 
when the steam port (which is denoted in the figure by the in- 
closed square containing diagonal lines) is full open, as shown 
on the diagram at 2. 

The diameter of the circle B being equal to the full stroke 
of valve, it is evident that from the point 4 we may mark off 
with the compasses the position of the crank-pin when the 
valve is at the end of its travel, such position being shown at 3. 

The edge of the valve now stands at H but parallel to D, 
and it is obvious that when it retreats to Jit will begin to close 
the latter, hence from /we mark A the position of the crank- 
pin, where the steam port begins to close. 



92 

"When the edge of the valve meets the edge D of the steam 
port again, the latter will be closed, and the expansion of the 
steam in the cylinder will begin ; hence we place the B point 
of compasses at J, and mark on A the position of crank -pin 
when the expansion begins, that position being shown at 5. 
The expansion will continue while the valve travels with its 
lap covering the steam port, which, being in this case f of an 
inch, is from J to K. 

As the edge of the valve, which is parallel to the line C, 
at the point K leaves K, the port (which is still the same 
port F) opens for the exhaust ; hence we mark the line i, 
whose length equals the width of the steam port, and which 
now represents the port as an exhaust port exactly as Fdid 
for a steam port. 

From iTwe mark the crank-pin position when the exhaust 
begins, which is shown at 6. 

When the valve-edge has moved across the port, the latter 
will be open full as an exhaust port ; hence with the B point 
at If we mark on A the position 7 of crank-pin, it then being 
on its other dead-centre. 

The exhaust is already full open, and it continues so while 
the valve passes to the end of its travel and returns to the edge 
of the port ; hence we place the B point at N (the end of 
valve travel), and mark position of crank-pin at 8. 

Continuing around the circle, we place compass-point at 0, 
which represents the edge of the port denoted by L (which is 
virtually the same point in the valve movement as is the valve 
If), and mark on A position 9, which is the position of the 
crank-pin when the exhaust begins to close. With the com- 
passes on B at P we mark on A point 10, which is the position 
of the crank pin when the exhaust closes and the compression 
or cushioning of the steam in the cylinder begins, it continu- 
ing until the crank-pin arrives at position 1, from whence it 
started. 



We have now to ascertain the position of the engine piston 
when the crank-pin was at each respective point, which is 
easily done, as follows : — 

The full stroke of the piston is represented by the diameter 
of circle A, and hence by the distance between the vertical 
lines Q B, Q representing the end from which the piston 
started ; hence we draw the vertical lines shown from each 
crank-pin position, and their distance from Q is the distance 
the piston has traveled when the crank-pin was in the respec- 
tive positions ; but as the circle A is one-eighth full size, we 
multiply the distance actually shown on the diagram by 8, 
and thus obtain from our diagram the following reading : — 

Steam-port full open when piston had moved 3| inches. 

Valve at end of travel when piston had moved of inches. 

Steam-port began to close when piston had moved 9| inches. 

Expansion began when piston had moved 18^ inches. 

Expansion ended and exhaust began when piston had moved 
22£ inches. 

Port full open as an exhaust-port when piston arrived at 
end of stroke. 

Exhaust remained open till piston had traveled 18^ inches 
of return-stroke, when it began to close. 

Exhaust closed when piston had moved 22^- inches of return- 
stroke. 

The compression and cushion took place during the last 1£ 
inches of piston movement. 

It is to be observed, however, that the angularity of the 
piston rod would cause a slight variation in the above data, 
the amount depending on the length of the connecting-rod in 
proportion to the length of the piston stroke. The effect of 
the variation would be to place positions 2, 3, and 4 further 
in advance than in the diagram, and positions 5 and 6 a little 
further back when the valve was in the respective positions ; 



94 

"while positions 9 and 10 would be placed slightly further to 
the left or in advance. 

It will he noted that in this case we have not given the 
valve any lead ; hut all that is necessary to take lead into ac- 
count is to mark to the right of D another line distant from D 
to the amount of the lead, in w r hich case D will represent the 
edge of the port and the new line the edge of the valve. The 
compass points being set from 1 to the intersection of the 
new line with the circle A, this will throw the points 2, 3, 
4, 5, and 6 further back towards 1. For the exhaust side we 
mark a new line to the left of line If, 0, using its junction 
•with B as the point of full port opening for exhaust ; this will 
throw the point M nearer to 1 and the point also nearer 
to 1. The positions of the port, as represented both at i^and 
Z, however, must remain with their nearest edges distant re- 
spectively from G to an amount equal to the lap only of the 
valve. 

In our example no exhaust lap was given to the valve, but 
had it been otherwise we should require to mark to the left of 
line C another vertical line distant from C to the amount of 
exhaust lap, and the junction of this new line with the circle 
B would be the point wherefrom to mark off position 6, or, in 
other words, the position of the crank-pin when the exhaust- 
port opened, and also the point (in place of P) wherefrom to 
mark off crank-pin, position 10 where the compression or 
cushioning began, the position of port L remaining as in the 
diagram. 

If, as is sometimes the case, a diagram thus laid out would 
have the circle B larger than A, if the latter be drawn to a 
scale of £, it may be drawn to a scale of \ or any other scale 
that will make A larger than B, but in any case the scale 
must be used as a multiplier in finding the position of the pis- 
ton from the end of the stroke. 



95 




SETTING ECCENTRICS. 

To set eccentrics upon a shaft before it is placed in the en- 
gine or to set them -without moving the engine, proceed as 
follows: If the engine runs one way only, and therefore has 
but one eccentric, set the crank-shaft in such a position that 
a wooden straight-edge can be placed 
sufficiently beneath it to be out of 
the way of the eccentric. Place the 
centre line of the length of the crank 
truly horizontal, which may be done 
as follows : From the centre of the 
crankshaft strike a circle of the dia- 
meter of the crank-pin, as shown in 
Fig. 32, at A, and draw upon the 
face of the crank a line that shall just 

meet the two circles as denoted by the line B, in Fig. 32, 
using a straight-edge, one end of which rests upon the crank- 
pin, while the other end is coincident with the perimeter of 
the circle A. 

By means of the wedges shown at (7, adjust the crank until 
the line B stands horizontally level, tested by a spirit-level. 
Then take a straight-edge, as in 
Fig. 33, and draw on it the line F, 
and place it horizontally level be- 
neath the crank-shaft and the ec- 
centric, fixing it temporarily so 
that it will not be liable to move. 
To find the centre of the crank- 
shaft 0, hang over it plumb-lines 
as denoted by the lines E 7, and 
where the plumb-lines intersect 
the line F, mark the points J K, 
and midway between J K is the 




96 



centre of the shaft marked on the straight-edge at L. From 
X, mark on the line F the point J/, distant from L the amount 
equal to the lap of the valve added to the amount of lead the 
valve is required to have. From the point M mark on the 
line Fthe diameter of the eccentric producing the points NO ; 
then hang over the circumference of the eccentric the plumb- 
lines P Q, and when these lines coincide with the points JV 
on i^the eccentric is in its proper position. 

Here, however, it is necessary to point out that in marking 
the point Mit is necessary to consider which way the engine 
is to run. In Fig. 33 the arrow denotes the direction of the 
crank revolution, hence M is located on the right side of X, 
for M must, in an engine in which the slide valve gear has 
no rock-shaft, always be placed on the right of L farthest from 
the crank-pin, no matter at which end of the stroke the crank 
stands, or in which direction it is to run. But in engines hav- 
ing a rock-shaft, iWruust be placed on the side of L nearest to 
the crank-pin. 

In Fig. 34 is shown the operation applied to an engine, such 
as a locomotive, having two eccentrics in order to enable it 
to run in either direction. In this case 
it is necessary to remember that the 
eccentric that is to operate the valve 
for the engine to run forward (that is 
in the direction denoted by the arrow 
in Fig. 34) must be the one that stands 
with its throw line following the crank, 
as shown at Bin Fig. 34, in which the 
engine is supposed to have a rock- 
shaft, hence M is on the crank-pin 
side of L. The position of the back- 
ward eccentric,, with relation to the 
crank, is precisely the same as ec- 
centric E, save that its throw line, 8, is as much one side of 



Fig. 34. 




97 

the crank as R's throw line is on the other, hence the plumb- 
lines P, Q, will intersect the points JV, 0, when placed on 
either eccentric. The eccentric that has its throw line in ad- 
vance of the crank is called the leading one, hence in Fig. 34, 
S leads. In English engines the left hand eccentric leads, 
while in the United States the right hand one leads. If the 
wrong one is made to lead, the result will be that the engine 
will run backwards when the reversing lever is placed to run 
forward, and vice versa. 

Beferring again to Fig. 33, to cause the crank to revolve the 
other way all that would be necessary is to move the eccentric 
so that its throw line R stands in the direction denoted by 8, 
hence R in Fig. 33 and R in Fig. 34 represent the eccentric 
set to run forward in both cases, one engine having, and the 
other not having, a rock-shaft. When the line of direction of 
the eccentric rod is not a line parallel with the centre line of 
the bore of the cylinder (which it usually is), the crank must 
be placed on the dead centre as before, but instead of the line 
F being adjusted to the centre-line of the crank, it must be 
adjusted to the centre-line of the eccentric-rod connection, the 
process being shown in Fig. 35, in which the engine is sup- 
posed to have a rock-shaft A connected to the slide spindle at 
one end, and to the eccentric-rod at the other. Hence the line 
of eccentric-rod connection is represented by the line B. In- 
stead of carrying the centre-line of the shaft down vertically 
to the line F, standing horizontally, we must place the 
straight-edge at a right angle to B, and use a square as shown 
in the figure, instead of the plumb-lines, the rest of the opera- 
tion remaining in all other respects the same. 



98 



Fie. 35. 




INDEX. 



PA3E 

Angular advance or lead of an ec- 
centric 9, 42, 43 

Angularity of the connecting rod 18 

Area of steam ports 63 

Auchincloss, W. S 70 

Automatic cut-off slide valve 5 

Bochet, M. H 85 

Bridges, width of 36, 68, 74 

Bourne, John 68 

Burgh, N. P 69 

Clearance, a ction of 31 

Clearance, description of 30 

Coefficient of friction 81-88 

Compression 59, 63 

Conditions under which a slide- 
valve operates 77 

Connecting rod, angularity of.. 18, 43 
Connecting rod, effects of angu- 
larity of 20 

Crank, movement 21 

Crank, quarter revolutions of . . . 21 

Crank, speed of 19 

Cut-off, point of 37 

Cut-off slide valve 5 

Cylinder, exhaust, contraction 
of 27,35 

Eccentric, angular advance of 8, 42, 43 
Eccentric, effect of valve travel 

on the 34 

Eccentric, piston aad crank move- 
ments 21 

Eccentrics, setting double 96 

Eccentrics, setting single 95 

Expansion, advantages of 14 

Exhaust area during different 

periods of the stroke 65 

Exhaust area in proportion to 

steam area 63, 66 

Exhaust, back pressure on 54 

Exhaust lap, when employed.... 29 



PAGE 

Exhaust side of the valve, lap on 25 

Expansion, comparisons of 60 

Expansion of steam in the steam 

passages 61 

Friction, coefficient of S4-88 

Lap, action of steam 15 

Lap, advantages of steam 15 

Lap, exhaust 9, 25, 26, 27 

Lap, exhaust, when employed. . . 29 

Lap, measurement of 14 

Lap of a valve 13 

Lap of the steam side of the valve 13 

Lap, steam 13, 25 

Lap, steam, the effects of 26, 27 

Lap, without 5 

Lead of an eccentric 9, 42, 43 

Lead of valve, determination of . 8 
Locomotive practice, examples of 

valve movements from 44-56 

Locomotive slide valve, illustra- 
tion of 80 

Locomotives, use of slide valve in 5 
Lubrication of slide valves ... 88, 89 

Piston, eccentric and crank move- 
ments 21 

Piston, variations in velocity of 19, 22 

Point of cat-off 37 

Point of release 38 

Ports, areas, proportion of ex- 
haust to steam 66 

Ports, effective area of 28 

Ports, exhaust 6 

Ports, opening of 24 

Ports, proportioning area of 59, 68, 72 

Ports, shape of 68 

Ports, steam . . .• 6 

Ports, variations in opening and 

closure of 17 

Power required to operate a slide 

valve ' 76 

(99) 



100 



PAGE 

Results of comparison of valve 
movements 57-68 

Rock-shaft, diagram showing ef- 
fects of 41 

Rock- shaft, effect of, on eccentric 
position 40 

Setting eccentrics 95-9S 

Shape of steam ports 68 

Slide valve, engines to which ap- 
plied 5 

Slide valve, meaning of term 5 

Slide valve, simplest form of 5 

Stationary engines, automatic cut- 
off valves in 5 

Steam, expansion of 15, 23 

Steam lap 13 

Steam ports, area and shape of . . 68 

Steam ports, proportioning 72 

Steam ports, shape of 68 

Steam side of the valve, lap of . . 13 

Steam supply 9 

Steam, using expansively 14 

Tab'es of comparison of valve 
movements, 58, 59, 60, 61, 62, 63, 65, 



Valve, conditions under which it 

operates 77 

Valve, diagram of action of 10 



PAGE 

Valve, illustration of an ordinary 

locomotive 80 

Valve, lap on the exhaust side of 26 

Valve, lead 7, 8, 9 

Valve movements, comparisons 

of, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 

67, 68 

Valve movements, examples of, 44, 45, 

46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56 

Valve travel 7, 32, 51, 75, 29 

Valve, wearing surface of a 67 

Valves, comparisons of different . 39 
Valves, finding working results 

of 89-94 

Valves, fit of, to their seats 77 

Valves, friction of 84 

Valves, lubrication of 88, S9 

Valves, power required to move, 73, 
76 

Valves, pressure on 80 

Valves, spring of 81 

Valves, surfaces of 77 

Valves, warping of 78, 79 

Width of bridges 36, 68, 74 

"Without lap 5 

"Workinsr results of a slide valve, 
method of finding S9-94 

Zeuner, Dr : 69 



CATALOGUE 

PRACTICAL Al illTIMC BOOKS, 



PUBLISHED BIT 



HMRY CAREY BAIBD & CO, 

Industrial Publishers and Booksellers, 
NO. 810 WALNUT STREET, 



PHILADELPHIA, 



tiSf Any of the Books comprised in this Catalogue will be sent by mail, free of 
postage, at the publication price. 

*$* A Descriptive Catalogue, 96 pages, 8vo,, will be sent, free of postage, to any 
one who will furnish the publisher with his address. 



ARLOT.— A Complete Guide for Coach Painters. 

Translated from the French of M. Arlot, Coach Painter ; for eleven 
years Foreman of Painting to M. Eherler, Coach Maker, Paris. By 
A. A. Fesquet, Chemist and Engineer. To which is added an Ap- 
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Practice of Coach and Car Painting and Varnishing in the United 
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ARMENGAUD, AMOROUX, and JOHNSON.— The 
Practical Draughtsman's Book of Industrial De- 
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Forming a Complete Course of Mechanical Engineering and Archi- 
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Armengaud the younger, and Amoroux, Civil Engineers. Rewritten 
and arranged with additional matter and plates, selections from and 
examples of the most useful and generally employed mechanism of 
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Practical Mechanic's Journal." Illustrated by 50 folio steel plates, 
and 50 wood-cuts. A new edition, 4to. .... $10.00 

1 



2 HENRY CAEEY BAIED'S CATALOGUE. 

ARROWSMITH- Paper-Hanger's Companion : 

A Treatise in which the Practical Operations of the Trade are Sys- 
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Observations and Directions for the Panelling and Ornamenting of 
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ASHTON .— The Theory and Practice of the Art of De- 
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Giving full Instructions for Reducing Drafts as well as the Methods 
of Spooling and Making out Harness for Cross Drafts, and Finding 
any Required Reed, with Calculations and Tables of Yarn. Bv 
Frederick T. Ashton, Designer, West Pittsfieid, Mass. With 52 
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BAIRD. — Letters on the Crisis, the Currency and the 
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By Henry Carey Baird. Pamphlet 05 

BAIRD. — Protection of Home Labor and Home Pro- 
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By Henry Carey Baird. 8vo., paper 10 

BAIRD.— Some of the Fallacies of British Free-Trade 
Revenue Reform. 

Two Letters to Arthur Latham Perry, Professor of History and Politi- 
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Pamphlet 05 

BAIRD.— The Rights of American Producers, and the 
Wrongs of British Free- Trade Revenue Reform. 
By Henry Carey Baird. Pamphlet 05 

BAIRD.— Standard Wages Computing Tables : 

An Improvement in all former Methods of Computatior , so arranged 
that wages for days, hours, or fractions of hoars, at a specified rate p< r 
day or hour may be ascertained at a glance. By T. Spangler Baird. 
Oblong folio ^5.00 

BAIRD.— The American Cotton Spinner, and Mana- 
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A Practical Treatise on Cotton Spinning; giving the Dimensions and 
Speed of Machinery, Draught and Twist Calculations, etc. ; with 
notices of recent Improvements : together with Rules and Examples 
for making changes in the sizes and numbers of Roving and Yarn. 
Compiled from the papers of the late Robert H. Baird. 12mo. $1.50 



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BAKER.— Long-Span Railway Bridges : 
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BATJERMAN.— A Treatise on the Metallurgy of Iron : 
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Royal School of Mines. First American Edition, Revised and En- 
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from the Report of Abeam S. Hewitt, U. S. Commissioner to the 
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BEANS.— A Treatise on Railway Curves and the Loca- 
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Targes. Illustrated by 33 plates, comprising nearly 200 figures. By 
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BELL.— Chemical Phenomena of Iron Smelting : 

An Experimental and Practical Examination of the Circumstances 
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of the Air, and the proper Condition of the Materials to be operated 
upon. By I. Lowthian Bell. Illustrated. 8vo. . . $6.00 

BEMROSE— Manual of Wood Carving : 

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BICKNELL.— Village Builder, and Supplement : 

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BLENKARN— Practical Specifications of Works exe- 
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BLINN.— A Practical Workshop Companion for Tin, 
Sheet- Iron, and Copperplate Workers : 

Containing Rules for describing various kinds of Patterns used by 
Tin, Sheet-Iron, and Copper-plate Workers; Practical Geometry*; 
Mensuration of Surfaces and Solids ; Tables < f the Weights of Metals, 
Lead Pipe, etc. ; Tables of Areas and Circumferences of Circles ; 
Japan. Varnishes, Lackers, Cements, Compositions, etc., etc. By 
Leeoy J. Blinn, Master Mechanic. With over 100 Illustrations. 
12mo $2.50 

BOOTH.— Marble Worker's Manual: 

Containing Practical Information respecting Marbles in general, their 
Cutting, "Working, and Polishing; Veneering of Marble; Mosaics: 
Composition and Use of Artificial Marble, Stuccos, Cements, Receipts, 
Secrets, etc., etc. Translated from the French by M, L. BOOTH. 
With an Appendix concerning American Marbles. 12mo., cloth. $1.50 

BOOTH AND MORFIT.— The Encyclopedia of Che- 
mistry, Practical and Theoretical : 

Embracing its application to the Arts, Metallurgy, Mineralogy, Ge- 
ology, Medicine, and Pharmacy. By James C. Booth, Melter and 
Refiner in the United States Mint, Professor of Applied Chemistry in 
the Franklin Institute, etc., assisted by Campbell Moefit, author 
of " Chemical Manipulations," etc. Seventh edition. Royal Svo., 
978 pages, with numerous wood-cuts and other illustrations. . £5.00 

BOX.— A Practical Treatise on Heat: 

As applied to the Useful Arts ; for the Use of Engineers, Architects, 
etc. By Thomas Box, author of " Practical Hydraulics." Illustrated 
by 14 plates containing 114 figures. 12mo $5.00 

BOX.— Practical Hydraulics : 

A Series of Rules and Tables for the use of Engineers, etc. By 
Thomas Box. 12mo $2.5*0 

BROWN.— Five Hundred and Seven Mechanical 

Movements : 
Embracing all those which are most important in Dynamics, Hydrau- 
lics, Hydrostatics, Pneumatics, Steam Engines, Mill and other Gear- 
ing, Presses, Horologv, and Miscellaneous Machinery ; and including 
raanv movements never before published, and several of which have 
only" recently come into use. By Henry T. Brown, Editor of the 
" American Artisan." In one volume, 12mo. . . . $1.00 



HENRY CAREY BAIRD'S CATALOGUE. 5 

BITCKMASTER- The Elements of Mechanical Phy- 
sics : 

By J. C. Buckmaster, late Student in the Government School of 
Mines ; Certified Teacher of Science by the Department of Science 
and Art ; Examiner in Chemistry and Physics in the Royal College 
of Preceptors ; and late Lecturer in Chemistry and Physics of the 
Royal Polytechnic Institute. Illustrated with numerous engravings. 
In one volume, 12mo. . . $1.50 

BULLOCK.— The American Cottage Builder : 

A Series of Designs, Plans, and Specifications, from $200 to $20,000, 
for Homes for the People ; together with Warming, Ventilation, 
Drainage, Painting, and Landscape Gardening. By John Bullock, 
Architect, Civil Engineer, Mechanician, and Editor of " The Rudi- 
ments of Architecture and Building," etc., etc. Illustrated by 75 en- 
gravings. In one volume, 8vo $3.50 

BULLOCK. — The Rudiments of Architecture and 
Building : 

Eor the use of Architects, Builders, Draughtsmen, Machinists, Engi- 
neers, and Mechanics. Edited by John Bullock, author of " The 
American Cottage Builder." Illustrated by 250 engravings. In one 
volume, 8vo $3.50 

BURGH. — Practical Illustrations of Land and Marine 
• Engines : 

Showing in detail the Modern Improvements of High and Low Pres- 
sure, Surface Condensation, and Super-heating, together witd Land 
•and Marine Boilers. By N. P. Burgh, Engineer. Illustrated by 
20 plates, double elephant folio, with text . . . . . $21.00 

BURGH.— Practical Rules for the Proportions of Mo- 
dern Engines and Boilers for Land and Marine 
Purposes. 

By K P. Burgh, Engineer. 12mo. . ,,.'•;, . . $1.50 

BURGH— The Slide- Valve Practically Considered. 

By N. P. Burgh, Engineer. Completely illustrated. 12mo. $2.00 

BYLES.— Sophisms of Free Trade and Popular Politi- 
cal Economy Examined. 
By a Barrister (Sir John Barnard Byles, Judge of Common 
Pleas). First American from the Ninth English Edition, as published 
by the Manchester Reciprocity Association. In one volume, 12mo. 
Paper, 75 cts. Cloth . . . . . . . . $1.25 

PYRTT.— The Complete Practical Brewer : 

Or Plain, Accurate, and Thorough Instructions in the Art of Brewing 
Beer, Ale, Porter, including the Process of making Bavarian Beer, 
all the Small Beers, such as Root-beer, Ginger-pop, Sarsaparilla- 
beer, Mead, Spruce Beer, etc., etc. Adapted to the use of Public 
Brewers and Private Families. By M. La Fayette Byrn, M D. 
With illustrations. 12mo , $1.25 



HENRY CAREY BAIED'S CATALOGUE. 



B YEN.- The Complete Practical Distiller : 

Comprising the most perfect and exact Theoretical and Practical De- 
scription of the Art of Distillation and Rectification ; including all of 
the most recent improvements in distilling apparatus; instructions 
for preparing spirits from the numerous vegetables, fruits, etc.; direc- 
tions for the distillation and preparation of all kinds of brandies and 
other spirits, spirituous and other compounds, etc., etc. By M. La 
Fayette Byrn, M. D. Eighth Edition. To which are added, Prac- 
tical Directions for Distilling, from the French of Th. Flin?, Brewer 
and Distiller. 12mo $1.50 

BYRNE.— Handbook for the Artisan, Mechanic, and 
Engineer : 

Comprising the Grinding and Sharpening of Cutting Tools, Abrasive 
Processes, Lapidary Work, Gem and Glass Engraving, Varnishing 
and Lackering, Apparatus, Materials and Processes for Grinding and 
Polishing, etc. By Oliver Byexe. Illustrated bv 185 wood en- 
gravings. In one volume, Svo . $5.00 

BYRNE— Pocket Book for Railroad and Civil Engi- 
neers : 

Containing New, Exact, and Concise Methods for Laying out Rail- 
road Curves, Switches, Frog Angles, and Crossings"; the Staking 
out of work ; Levelling ; the Calculation of Cuttings ; Embankments ; 
Earth-work, etc. By Oliver Byexe. ISmo., full bound, pocket- 
book form $1.75 

BYRNE.— The Practical Model Calculator : 

For the Engineer, Mechanic, Manufacturer of Engine Work, Naval 
Architect, Miner, and Millwright. By Oliver Byrne. 1 volume, 
8vo., nearly GOO pages $4.50 

BYRNE.— The Practical Metal-Worker's Assistant: 

Comprising Metallurgic Chemistry ; the Arts of Working all Metals 
and Alloys ; Forging of Iron and Steel ; Hardening and Tempering ; 
Melting and Mixing; Casting and Founding; Works in Sheet Metal; 
The Processes Dependent on the Ductility of the Metals; Soldering; 
and the most Improved Processes and Tools employed by Metal- 
workers. With the Application of the Art of Electro-Metallurgy to 
Manufacturing Processes ; collected from Original Sources, and from 
the Works of Holtzapffel, Bergeron, Leupold, Plumier, Napier, 
Scoffern, Clay, Fairbairn, and others. By Oliver Byexe. A new, 
revised, and improved edition, to which is added An Appendix, con- 
taining The Manufacture of Russian Sheet-Irox. By John 
Percy, M. D., F.R.S. The Maxufacture of Malleable Ieox 
Castixgs, and Improvfmexts ix Bessemer Steel. By A. A. 
Fesquet, Chemist and Engineer. With over 600 Engravings, illus- 
trating every Branch of the Subject. 8vo $7.00 

Cabinet Maker's Album of Furniture: 

Comprising a Collection of Designs for Furniture. Illustrated by 48 
Large and Beautifully Engraved Plates. In one vol., oblong $3.50 



HENRY CAREY BAIRD'S CATALOGUE. 7 

CALLINGHAM.— Sign Writing and Glass Emboss- 
ing: 

A Complete Practical Illustrated Manual of the Art. By James 
Callingham. In one volume, 12mo $1.50 

C AMPIN. — A Practical Treatise on Mechanical Engi- 
neering : 

Comprising Metallurgy, Moulding, Casting, Forging, Tools, Work- 
shop Machinery, Mechanical Manipulation, Manufacture of Steam- 
engines, etc., etc. With an Appendix on the Analysis of Iron and 
Iron Ores. By Francis Campin, C. E. To which are added, Obser- 
vations on the Construction of Steam Boilers, and Remarks upon 
Furnaces used for Smoke Prevention ; with a Chapter on Explosions. 
By R. Armstrong, C. E., and John Bourne. Rules for Calculating 
the Change Wheels for Screws on a Turning Lathe, and for a Wheel- 
cutting Machine. By J. La Nicca. Management of Steel, Includ- 
ing Forging, Hardening, Tempering, Annealing, Shrinking, and Ex- 
pansion. And the Case-hardening of Iron. By G. Ede. 8vo. Illus- 
trated with 29 plates and 100 wood engravings . . . $6.00 

CAMPIN.— The Practice of Hand-Turning in Wood, 
Ivory, Shell, etc. : 

With Instructions for Turning such works in Metal as may be re- 
quired in the Practice of Turning Wood, Ivory, etc. Also, an Appen- 
dix on Ornamental Turning. By Feancis Campin; with Numerous 
Illustrations. 12mo., cloth . . . . " . . $3.00 

CARE Y — The Works of Henry C. Carey : 
FINANCIAL CRISES, their Causes and Effects. 8vo. paper . 25 
HARMONY OF INTERESTS: Agricultural, Manufacturing, and 

Commercial. 8vo., cloth $1.50 

MANUAL OF SOCIAL SCIENCE. Condensed from Carey's " Prin- 
ciples of Social Science." By Kate McKean. 1 vol. 12mo. $2.25 
MISCELLANEOUS WORKS : comprising " Harmony of Interests," 
" Money," " Letters to the President," " Financial Crises," " The 
Way to Outdo England Without Fighting Her," "Resources of 
the Union," "The Public Debt," "Contraction or Expansion?" 
"Review of the Decade 1857-67," "Reconstruction," etc., etc. 
Two vols., 8vo., cloth 

PAST, PRESENT, AND FUTURE. 8vo $2.50 

PRINCIPLES OF SOCIAL SCIENCE. 3 vols., 8vo., cloth $10.00 

THE SLAVE-TRADE, DOMESTIC AND FOREIGN ; Why it Ex~ 

ists, and How it may be Extinguished (1853). 8vo., cloth . $2.00 

LETTERS ON INTERNATIONAL COPYRIGHT (1867) . 50 

THE UNITY OF LAW : As Exhibited in the Relations of Physical, 

Social, Mental, and Moral Science (1872). In one volume, 8vo., 

pp. xxiii., 433. Cloth $3.50 

CHAPMAN.— A Treatise on Ropemaking : 

As Practised in private and public Rope yards, with a Description 
of the Manufacture, Rules, Tables of Weights, etc., adapted to the 
Trades, Shipping, Mining, Railways, Builders, etc. By Robert 
Chapman. 24mo $1.50 



8 HENKY CAEEY BAIRD'S CATALOGUE. 

COLBURN— The Locomotive Engine : 

Including a Description of its Structure, Rules for Estimating its Capa- 
bilities, and Practical Observations on its Construction and Manage- 
ment. By Zerah Colburn. Illustrated. A new edition. 12mo. $1.25 

CBAIK.— The Practical American Millwright and 
Miiler. 
By David Craik, Millwright. Illustrated by numerous wood en- 
gravings, and two folding plates. 8vo $5.00 

DE GRAFF.— The Geometrical Stair Builders' Guide : 

Being a Plain Practical System of Hand-Railing, embracing all its 
necessary Details, and Geometrically Illustrated by 22 Sieel Engrav- 
ings ; together with the use of the most approved principles of Prac- 
tical Geometry. By Simon De Graff, Architect. 4to. . $5.00 

DE KONINCK.— DIETZ.— A Practical Manual of Che- 
mical Analysis and Assaying : 

As applied to the Manufacture of Iron from its Ores, and to Cast Ir<an, 
Wrought Iron, and Steel, as found in Commerce. By L. L. De Kon- 
INCK, Dr. Sc, and E. Dietz, Engineer. Edited with Notes, by Robert 
Mallet, F.R.S., F.S.G., M.I.C.E., etc. American Edition, Edited 
with Notes and an Appendix on Iron Ores, by A. A. Fesquet, Chemist 
and Engineer. One volume, 12mo $2.50 

DUNCAN.— Practical Surveyor's Guide: 

Containing the necessary information to make any person, of common 
capacity, a finished land surveyor without the aid of a teacher. By 
Andrew Duncan. Illustrated. 12mo., cloth. . . . $1.25 

DUPLAIS.— A Treatise on the Manufacture and Dis- 
tillation of Alcoholic Liquors : 

Comprising Accurate and Complete Details in Regard to Alcohol from 
Wine, Molasses, Beets, Grain, Rice, Potatoes, Sorghum, Asphodel, 
Fruits, etc. ; with the Distillation and Rectification of Brandy, Whis- 
key, Rum, Gin, Swiss Absinthe, etc., the Preparation of Aromatic Wa- 
ters, Volatile Oils or Essences, Sugars, Syrups, Aromatic Tinctures, 
Liqueurs, Cordial Wines, Effervescing Wines, etc., the Aging of Brandy 
and the Improvement of Spirits, with Copious Directions and Tables 
for Testing and Reducing Spirituous Liquors, etc., etc. Translated 
and Edited from the French of MM. DUPLAIS, Aine et Jeune. By 
M. McKennie, M.D. To which are added the United States Internal 
Revenue Regulations for the Assessment and Collection of Taxes on 
Distilled Spirits. Illustrated by fourteen folding plates and several 
wood engravings. 743 pp., 8vo $10.00 

DUSSATJCE.— A General Treatise on the Manufacture 
of Every Description of Soap : 

Comprising the Chemistry of the Art, with Remarks on Alkalies, Sa- 
ponifiable Fatty Bodies, the apparatus necessary in a Soap Factory, 
Practical Instructions in the manufacture of the various kinds of Son}), 
the assay of Soaps, etc., etc. Edited from Notes of Larme, Fontenelle, 
Malapayre, Dufour, and others, with large and important additions by 
Prof. H. DUSSAUCE, Chemist. Illustrated. In one vol., 8vo. . $12.50 



HENRY CAREY BAIRD'S CATALOGUE. 9 

DUSSAUCE.— A General Treatise on the Manufacture 
of Vinegar : 

Theoretical aud Practical. Comprising the various Methods, by the 
!Slo\v and the Quick Processes, with Alcohol, Wine, Grain, Malt, Cider, 
Molasses, and Beets ; as well as the Fabrication of Wood Vinegar, etc., 
e;c. By Prof. H. Dussauce. In one volume, 8vo. . . $5.00 

DUSSAUCE.— A New and Complete Treatise on the 
Arts of Tanning, Currying, and Leather Dressing : 

Comprising all the Discoveries and Improvements made in France, 
Great Britain, and the United States. Edited from Notes and Docu- 
ments of Messrs. Sallerou, Grouvelle, Duval, Dessables, Labarraque, 
Payen, Rene, De Fontenelle, Malapeyre, etc., etc. By Prof. H. Dus- 
sauce, Chemist. Illustrated by 212 wood engravings. 8vo. $25.00 

PUSSAUCE— A Practical Guide for the Perfumer : 

Being a New Treatise on Perfumery, the most favorable to the Beauty 
without being injurious to the Health, comprising a Description of the 
substances used in Perfumery, the Formula? of more than 1000 Prepa- 
rations, such as Cosmetics, Perfumed Oils, Tooth Powders, Waters, 
Extracts, Tinctures, Infusions, Spirits, Vinaigres, Essential Oils, Pas- 
tels, Creams, Soaps, and many new Hygienic Products not hitherto 
described. Edited from Notes and Documents of Messrs. Debay, Ln- 
nel, etc. With additions by Prof. H. Dussauce, Chemist. 12mo. 

DUSSAUCE.— Practical Treatise on the Fabrication 
of Matches, Gun Cotton, and Fulminating Powders. 

By Prof. H. Dussauce. 12mo $3.00 

Dyer and Color-maker's Companion: 

Containing upwards of 200 Receipts for making Colors, on the most 
approved principles, for all the various styles and fabrics now in exist- 
ence ; with the Scouring Process, and plain Directions for Preparing, 
Washing-off, and Finishing the Goods. In one vol., 12mo. . $1.25 

EASTON.— A Practical Treatise on Street or Horse- 
power Railways. 

Bv Alexander Easton, C.E. Illustrated by 23 plates. 8vo., 
cloth $3.00 

ELDER.— Questions of the Day : 

Economic and Social. By Dr. William Elder. 8vo. . $3.00 

FAIRBAIRTT.— The Principles of Mechanism and Ma- 
chinery of Transmission : 

Comprising the Principles of Mechanism, Wheels, and Pulleys, 
Strength and Proportions of Shafts, Coupling of Shafts, and Engaging 
and Disengaging Gear. Bv Sir William Fairbaien, C.E., LL.D., 
F.R.S., F.G.S. "Beautifully illustrated by over 150 wood-cuts. In 
one volume, 12mo. $2.50 

FORSYTH— "°>ook of Designs for Headstones, Mural, 
and other Monuments : 
Containing 78 Designs. By James Forsyth. With an Introduction 
by Charles Boutell, M. A. 4to., cloth $5.00 



10 HENEY CAREY BAIED'S CATALOGUE. 

_ 1 

GIBSON.— The American Dyer: 
A Practical Treatise on the Coloring of Wool, Cotton, Yarn and 
Cloth, in three parts. Part First gives a descriptive account of the 
Dye Stuffs ; if of vegetable origin, where produced, how cultivated, 
arid how prepared for use ; if chemical, their composition, specific 
gravities, and general adaptability, how adulterated, and how to de- 
tect the adulterations, etc. Part Second is devoted to the Coloring of 
"Wool, giving recipes for one hundred and twenty-nine different colors 
or shades, and is supplied with sixty colored samples of Wool. Part 
Third is devoted to the Coloring of" Raw Cotton or Cotton Waste, for 
mixing with Wool Colors in the Manufacture of all kinds of Fabrics, 
gives recipes for thirty-eight different colors or shades, and is supplied 
with twenty-four colored samples of Cotton Waste. Also, recipes for 
Coloring Beavers, Doeskins, and Flannels, with remarks upon Ani- 
lines, giving recipes for fifteen different colors or shades, and nine 
samples of Aniline Colors that will stand both the Fulling and Scour- 
ing process. Also, recipes for Aniline Colors on Cotton Thread, and 
recipes for Common Colors on Cotton Yarns. Embracing in all over 
two hundred recipes for Colors and Shades, and ninety-four samples 
of Colored Wool and Cotton Waste, etc. By Richard H. Gibson, 
Practical Dyer and Chemist. In one volume, 8vo. . . $6.00 

GILB ART. —History and Principles of Banking : 

A Practical Treatise. By James W. Gilbart, late Manager of the 
London and Westminster Bank. With additions. In one volume, 
8vo., 600 pages, sheep $5.00 

Gothic Album for Cabinet Makers : 

Comprising a Collection, of Designs for Gothic Furniture. Illustrated 
by 23 large and beautifully engraved plates. Oblong . . $2.00 

GRANT. — Beet-root Sugar and Cultivation of the 
Beet. 
By E. B. Geant. 12mo $1.25 

GREGORY.— Mathematics for Practical Men : 

Adapted to the Pursuits of Surveyors, Architects, Mechanics, and 
Civil Engineers. By Olinthus Geegoey. 8vo., plates, cloth $3.0(1 

GRISWOLD.— Railroad Engineer's Pocket Compan- 
ion for the Field : 

Comprising Rules for Calculating Deflection Distances and Angles, 
Tangential Distances and Angles, and all Necessary Tables for Engi- 
neers ; also the art of Levelling from Preliminary Survey to the Con- 
struction of Railroads, intended Expressly for the Young Engineer, 
together with Numerous Valuable Rules and Examples. By W. 
Geiswold. 12mo., tucks $1.75 

GRTJNER.— Studies of Blast Furnace Phenomena. 
By M. L. Getjnee, President of the General Council of Mines of 
France, and lately Professor of Metallurgy at the Ecole des Mines. 
Translated, with the Author's sanction, with an Appendix, by L. D. B. 
Gordon, F.R.S.E..F, G. S. Illustrated. 8vo. . . . $2.50 



HENRY CAREY BAIRD'8 CATALOGUE. 11 

GUETTIER.— Metallic Alloys : 

Being a Practical Guide to their Chemical and Physical Properties, 
their Preparation, Composition, and Uses. Translated from the 
French of A. Guettier, Engineer and Director of Foundries, author 
of" La Fouderie en France," etc., etc. . By A. A. Fesquet, Chemist 
and Engineer. In one volume, 12mo $3.00 

HARRIS. — Gas Superintendent's Pocket Companion. 

By Harris & Brother, Gas Meter Manufacturers, 1115 and 1117 
Cherry Street, Philadelphia. Full bound in pocket-book form $1.00 

Hats and Pelting: 

A Practical Treatise on their Manufacture. By a Practical Hatter. 
Illustrated by Drawings of Machinery, etc. 8vo. . . . $1.25 

HOFMATOT — A Practical Treatise on the Manufac- 
ture of Paper in all its Branches. 

By Carl Hofmann. Late Superintendent of paper mills in Ger- 
many and the United States ; recently manager of the Public Ledger 
Paper Mills, near Elkton, Md. Illustrated by 110 wood engravings, 
and five large folding j>lates. In one volume, 4to., cloth; 398 
pages $15.00 

HUGHES.— American Miller and Millwright's Assist- 
ant. 

By Wjnl Carter Hughes. A new edition. In one vol., 12mo. $1.50 

HURST.— A Hand-Book for Architectural Surveyors 
and others engaged in Building: 

Containing Formulae useful in Designing Builder's work, Table of 
Weights, of the materials used in Building, Memoranda connected 
with Builders' work, Mensuration, the Practice of Builders' Measure- 
ment, Contracts of Labor, Valuation of Property, Summary of the 
Practice in Dilapidation, etc., etc. By J. F. Hurst, C. E. Second 
edition, pocket-book form, full bound $2.00 

JEB.VIS.— Railway Property : 

A Treatise on the Construction and Management of Bailways ; de- 
signed to afford useful knowledge, in the popular style, to the" holders 
of this class of property; as well as Railway Managers, Officers, and 
Agents. By John B/Jervjs, late Chief Engineer of the Hudson 
Biver Railroad, Croton Aqueduct, etc. In one vol., 12mo., cloth $2.00 

JOHNSTON.— Instructions for the Analysis of Soils, 
Limestones, and Manures. 

By J. F. W. Johnston. 12mo 



12 HENEY CAREY BAIRD'S CATALOGUE. 

KEEKE.-A Hand-Book of Practical Gauging : 

For the Use of Beginners, to which is added, A Chapter on Distil la. 
tion, describing the process in operation at the Custom House for 
ascertaining the strength of wines. By James B. Keene, of H. M. 
Customs. 8vo . . . . $1.25 

KELTjEY.— Speeches, Addresses, and Letters on In- 
dustrial and Financial Questions. 
By Hon. William D. Kelley, M. C. In one volume, 544 pages, 
8vo i I&00 

KENTISH.— A Treatise on a Box of Instruments, 

And the Slide Rule ; with the Theory of Trigonometiy and Loga- 
rithms, including Practical Geometry, Surveying, Measuring of Tim* 
ber, Cask and Malt Gauging, Heights, and Distances. By Thomas 
Kentish. In one volume. 12mo. §1.25 

KOBELL .— ERINT— Mineralogy Simplified : 

A short Method of Determining and Classifying Minerals, by means 
of simple Chemical Experiments in the Wet Way. Translated from 
the last German Edition of F. Von Kobell, with an Introduction to 
Blow-pipe Analysis and other additions. By Henei Ee.nl M. D., 
late Chief Chemist, Department of Agriculture, author of " Coal 0:1 
and Petroleum." In one volume, 12mo $2.5Q 

LArTDRIN .— A Treatise on Steel : 

Comprising its Theory, Metallurgy, Properties, Practical Working, 
and Use. By M. II. C. Landejn, Jr., Civil Engineer. Translated 
from the French, with Notes, by A. A. Fesquet, Chemist and Engi- 
neer. With an Appendix on the Bessemer and the Martin Processes 
for Manufacturing Steel, from the Report of Abram S. Hewitt, United 
States Commissioner to the Universal Exposition, Paris, 18G7. In one 
volume, 12mo. &3.00 

LARKIH. — The Practical Brass and Iron Pounder's 
Guide : 

A Concise Treatise on Brass Founding, Moulding, the Metals and their 
Alloys, etc. : to which are added Beceiit Improvements in the Manu- 
facture of Iron, Steel by the Bessemer Process, etc., etc. By James 
Lakkin, late Conductor of the Brass Foundry Department in Eeany, 
Neafie & Co's. Penn Works, Philadelphia. Fifth edition, revised, 
with Extensive additions. In one volume, 12mo. . . $2,25 

LEA VITT.— Facts about Peat as an Article of Fuel : 

With Kemarks upon its Origin and Composition, the Localities in 
which it is found, the Methods of Preparation and Manufacture, and 
the various Uses to which it is applicable ; together with many other 
matters of Practical and Scientific Interest. To which is added a chap- 
ter on the Utilization of Coal Dust with Peat for the Production of an 
Excellent Fuel at Moderate Cost, specially adapted for Steam Service. 
By T. II. Leavitt. Third edition. 12mo. ... $1.75 



HENRY CAREY BAIRD'S CATALOGUE. 13 

LEEOUX, C — A Practical Treatise on the Manufac- 
tu: e of Worsteds and Carded Yarns : 

Comprising Practical Mechanics, with Rules and Calculations applied 
to Spinning; Sorting, Cleaning, and Scouring Wools; the English 
and French methods of Combing, Drawing, and Spinning Worsteds 
and Manufacturing Carded Yarns. Translated from the French of 
Charles Leroux, Mechanical Engineer, and Superintendent of a 
Spinning Mill, by Horatio Paine, M. D., and A. A. Fesquet, 
Chemist and Engineer. Illustrated by 12 large Plates. To which is 
added an Appendix, containing extracts from the Reports of the Inter- 
national Jury, and of the Artisans selected by the Committee appointed 
by the Council of the Society of Arts, London, on Woollen and Worsted 
Machinery and Fabrics, as exhibited in the Paris Universal Exposi- 
tion, 1867. 8vo., cloth $5.00 

LESLIE (Miss).— Complete Cookery: 

Directions for Cookery in its Various Branches. By Miss Leslie. 
60th thousand. Thoroughly revised, with the addition of New Re- 
ceipts. In one volume, 12mo., cloth $1.50 

LESLIE (Miss).— Ladies' House Book: 
A Manual of Domestic Economy. 20th revised edition. 12mo., cloth. 

LESLIE (Miss).— Two Hundred Receipts in French 
Cookery. 

Cloth, 12mo. 

LIEBEB,.— Assayer's Guide : 
Or, Practical Directions to Assayers, Miners, and Smelters, for the 
Tests and Assays, by Heat and by Wet Processes, for the Ores of all 
the principal Metals, of Gold and Silver Coins and Allovs, and of 
Coal, etc. By Oscar M. Lieber. 12mo., cloth. . *. $1.25 

LOTH.— The Practical Stair Builder: 
A Complete Treatise on the Art of Building Stairs and Iland-Rails, 
Designed for Carpenters, Builders, and Stair-Builders. Illustrated 
with Thirty Original Plates. By C. Edward Loth, Professional 
Stair-Builder. One large 4to. volume. .... $10.00 

LOVE.— The Art of Dyeing, Cleaning, Scouring, and 
Finishing, on the Most Approved English and 
French Methods: 

Being Practical Instructions in Dyeing Silks, Woollens, and Cottons, 
Feathers, Chips, Straw, etc. Scouring and Cleaning Bed and Window 
Curtains, Carpets, Rugs, etc. French and English Cleaning, aiiv 
Color or Fabric of Silk, Satin, or Damask. By Thomas Love, a 
Working Dyer and Scourer. Second American Edition, to which are 
added GeneVal Instructions for the Use of Aniline Colors. In one 
volume, 8vo., 343 pages. $5.00 



14 HEXRY CAREY BAIRD'S CATALOGUE. 

MAIN and BROWN. — Questions on Subjects Con- 
nected with the Marine Steam-Engine : 

And Examination Papers : with Hints for their Solution. By Thomas 
J. Main, Professor of Mathematics, Royal Xaval College, and Thomas 
Beowx, Chief Engineer, R. X. 12nio*., cloth. . . . $1.50 

MAIN and BROWN.— The Indicator and Dynamo- 
meter : 

With their Practical Applications to the Steam-Engine. By Thomas 
J. Maix, M. A. F. R., Assistant Professor Royal Xaval College, Ports- 
mouth, and Thomas Brown, Assoc. Inst. C. E., Chief Engineer, R. 
N., attached to the Royal Xaval College. Illustrated. From the 
Fourth London Edition. 8vo $1.50 

MAIN and BROWN.— The Marine Steam-Engine. 

By Thomas J. Main, F. R. ; Assistant S. Mathematical Professor at 
the Roval Xaval College, Portsmouth, and Thomas Brown, Assoc. 
Inst. C." E., Chief Engineer R. X. Attached to the Royal Xaval Col- 
lege. Authors of " Questions connected with the Marine Steam-En- 
gine," and the " Indicator and Dynamometer." "With numerous Illus- 
trations. In one volume, 8vo. $5.00 

MARTIN.— Screw-Cutting Tables, for the Use of Me- 
chanical Engineers : 

Showing the Proper Arrangement of Wheels for Cutting the Threads 
of Screws of any required Pitch ; with a Table for Making the Uni- 
versal Gas-Pipe Thread and Taps. By "VV. A. Martin, Engineer. 
8vo .50 

Mechanics' (Amateur) Workshop: 

A treatise containing plain and concise directions for the manipula- 
tion of Wood and Metals, including Casting, Forging, Brazing, Sol- 
dering, and Carpentrv. Bv the author of the " Lathe and its Uses." 
Third edition. Illustrated". 8vo $3.00 

MOLESWORTH— Pocket-Book of Useful Formulae 
and Memoranda for Civil and Mechanical Engi- 
neers. 

By GriLFORD L. Molesworth, Member of the Institution of Civil 
Engineers, Chief Resident Engineer of the Ceylon Railway. Second 
American, from the Tenth London Edition. In one volume, full 
bound in pocket-book form §2.00 

NAPIER.— A System of Chemistry Applied to Dyeing. 
By James Xapter, F. C. S. A Xew and Thoroughly Revised Edi- 
tion. Completely brought up to the present state of the Science, incl ti- 
ding the Chemistry of Coal Tar Colors, by A. A. Fesquet, Chemist 
and Engineer. With an Appendix on Dyeing and Calico Printing, as 
shown at the Universal Exposition, Paris, 1867. Illustrated. In one 
Volume, 8vo., 422 pa^es $5.00 



HENRY CAREY BAIRD'S CATALOGUE. 15 

NAPIER.— Manual of Electro-Metallurgy : 

Including the Application of the Art to Manufacturing Processes. By 
James NAPIER. Fourth American, from the Fourth London edition, 
revised and enlarged. Illustrated by engravings. In one vol., 8vo. $2.00 

NASON.— Table of Reactions for Qualitative Chemical 
Analysis. 
By Henry B. Nason, Professor of Chemistry in the Rensselaer Poly- 
technic Institute, Troy, New York. Illustrated by Colors. . 63 

NEWBERY.— Gleanings from Ornamental Art of 
every style : 
Drawn from Examples in the British, South Kensington, Indian, 
Crystal Palace, an^ ^ther Museums, the Exhibitions of 1851 and 1862, 
and the best Engliui and Foreign works. In a series of one hundred 
exquisitely drawn Plates, containing many hundred examples. By 
Robert Newbeey. 4to $12.50 

NICHOLSON.— A Manual of the Art of Bookbinding : 

Containing full instructions in the different Branches of Forwa?ding, 
Gilding, and Finishing. Also, the Art of Marbling Book-edges and 
Paper. By James B. Nicholson. Illustrated, li'mo., cloth. $2.25 

NICHOLSON.— The Carpenter's New Guide: 

A Complete Book of Lines for Carpenters and Joiners. By Peter 
Nicholson. The whole carefully and thoroughly revised by H. K. 
Davis, and containing numerous new and improved and original De- 
signs for Roofs, Domes, etc. By Samuel Sloan, Architect. Illus- 
trated by 80 plates. 4to. 

NORMS.— A Hand-book for Locomotive Engineers 
and Machinists: 

Comprising the Proportions and Calculations for Constructing Loco- 
motives ; Manner of Setting Valves ; Tables of Squares, Cubes, Areas, 
etc., etc. By Septimus Norris, Civil and Mechanical Engineer. 
New edition. Illustrated. 12mo., cloth $1.50 

NYSTROM.— On Technological Education, and the 
Construction of Ships and Screw Propellers : 

For Naval and Marine Engineers. By John W. Nystrom, late Act- 
ing Chief Engineer, U. S. N. Secondedition, revised with additional 
matter. Illustrated by seven engravings. 12mo. . . $1.50 

O'NEILL.— A Dictionary of Dyeing and Calico Print- 
ing : 

Containing a brief account of all the Substances and Processes in use 
in the Art of Dyeing and Printing Textile Fabrics ; with Practical 
Receipts and Scientific Information. By Charles O'Neill, Ana- 
lytical Chemist ; Fellow of the Chemical Society of London ; Member 
of the Literary and Philosophical Society of Manchester ; Author of 
"Chemistry of Calico Printing and Dyeing." To which is added ah 
Essay on Coal Tar Colors and their application to Dyeing and Calico 
Printing. By A. A. Fesquet, Chemist and Engineer. With an Ap- 
pendix on Dyeing and Calico Printing, as shown at the Universal 
Exposition, Paris, 1867. In one volume, 8vo., 491 pages. . $5.00 



16 HENRY CAREY BAIRD'S CATALOGUE. 

ORTON— Underground Treasures : 

How and Where to Find Them. A Key for the Ready Determination 
of all the Useful Minerals within the United States. By James 
Orton, A. M. Illustrated, 12mo - $1.50 

OSBOR!N.— American Mines and Mining: 
Theoretically and Practically Considered. By Prof. H. S. Osborn. 
Illustrated by numerous engravings. 8vo. {In preparation.) 

OSBORN— The Metallurgy of Iron and Steel : 

Theoretical and Practical in all its Branches ; with special reference 
to American Materials and Processes. By H. S. Osborn, LL. D., 
Professor of Mining and Metallurgy in Lafayette College, Easton, 
Pennsylvania. Illustrated by numerous large folding plates and 
wood-engravings. 8vo. $15.00 

OVERMAN.— The Manufacture of Steel : 

Containing the Practice and Principles of Working and Making Steel. 
A Handbook for Blacksmiths and Workers in Steel and Iron, Wagon 
Makers, Die Sinkers, Cutlers, and Manufacturers of Files and Hard- 
ware, of Steel and Iron, and for Men of Science and Art, By Fred- 
erick Overman, Mining Engineer, Author of the " Manufacture of 
Iron," etc. A new, enlarged, and revised Edition. By A. A. Fesquet, 
Chemist and Engineer $1.50 

OVERMAN.— The Moulder and Pounder's Pocket 
Guide : 

A Treatise on Moulding and Founding in Green-sand, Dry-sand, Loam, 
and Cement; the Moulding of Machine Frames, Mill-gear, Hollow- 
ware, Ornaments, Trinkets, Bells, and Statues ; Description of Moulds 
for Iron, Bronze, Brass, and other Metals ; Plaster of Paris, Sulphur, 
Wax, and other articles commonly used in Casting; the Construction 
of Melting Furnaces, the Melting and Founding of Metals ; the Com- 
position of Alloys and their Nature. With an Appendix containing 
Receipts for Alloys, Bronze, Varnishes and Colors for Castings ; also, 
Tables on the Strength and other qualities of Cast Metals. By Fred- 
erick Overman, Mining Engineer, Author of " The Manufacture 
of Iron." With 42 Illustrations. 12mo $1.50 

Painter, Gilder, and Varnisher's Companion : 

Containing Rules and Regulations in everything relating to the Arts 
of Painting, Gilding, Varnishing, Glass-Staining, Graining, Marbling, 
Sign- Writing, Gilding on Glass, and Coach Painting and Varnishing ; 
Tests for the Detection of Adulterations in Oils, Colors, etc. ; and a 
Statement of the Diseases to which Painters are peculiarly liable, with 
the Simplest and Best Remedies. Sixteenth Edition. Revised, with 
an Appendix. Containing Colors and Coloring -Theoretical and 
Practical. Comprising descriptions of a great variety c( Additional 
Pigments, their Qualities and Uses, to which are added, Dryers, and 
Modes and Operations of Painting, etc. Together with Chevreul's 
Principles of Harmony and Contrast of Colors. 12mo., cloth. $1.50 



HENRY CAREY BAIRD'S CATALOGUE. 17 

PALLETT.— The Miller's, Millwright's, and Engineer's 
Guide. 
By Henry Pallett. Illustrated. In one volume, 12nio. • $3.00 

PERCY.— The Manufacture of Russian Sheet-Iron. 

By John Percy, M.D., F.R.S., Lecturer on Metallurgy at the Royal 
School of Mines, and to The Advanced Class of Artillery Officers at 
the Royal Artillery Institution, Woolwich; Author of " Metallurgy." 
With Illustrations. Svo., paper 50 cts. 

PERKINS.— Gas and Ventilation. 

Practical Treatise on Gas and Ventilation. With Special Relation to 
Illuminating, Heating, and Cooking by Gas. Including Scientific 
Helps to Engineer-students and others. With Illustrated Diagrams. 
By E. E. Perkins. i2mo., cloth $1.25 

PERKINS and STOWE.-A New Guide to the Sheet- 
iron and Boiler Plate Roller : 

Containing a Series of Tables showing the Weight of Slabs and Piles 
to produce Boiler Plates, and of the Weight of Piles and the Sizes of 
Bars to produce Sheet-iron; the Thickness of the Bar Gauge in 
decimals ; the Weight per foot, and the Thickness on the Bar or Wire 
Gauge of the fractional parts of an inch ; the Weight per sheet, and 
the Thickness on the Wire Gauge of Sheet-iron of various dimensions 
to weigh 112 lbs. per bundle; and the conversion of Short Weight 
into Long Weight, and Long Weight into Short. Estimated and col- 
lected by G. H. Perkins and J. G. Stowe $2.50 

PHILLIPS and DARLINGTON.— Records of Mining 
and Metallurgy ; 

Or Facts and Memoranda for the use of the Mine Agent and Smelter. 
By J. Arthur Phillips, Mining Engineer, Graduate of the Imperial 
School of Mines, France, etc., and John Darlington. Illustrated 
by numerous engravings. In one volume, 12mo. . . $1.50 

PRO TEAUX.— Practical Guide for the Manufacture 
of Paper and Boards. 

By A. Prote atjx, Civil Engineer, and Graduate of the School of Arts 
and Manufactures, and Director of Thiers' Paper Mill, Puy-de-D6me. 
With additions, by L. S. Le Normand. Translated from the French, 
with Notes, by Horatio Paine, A.B., M. D. To which is added a 
Chapter on the Manufacture of Paper from Wood in the United 
States, by Henry T. Brown, of the " American Artisan." Illus- 
trated by six plates, containing Drawings of Paw Materials, Machi- 
nery, Plans of Paper-Mills, etc., etc. Svo. $10.00 

REGNAULT.— Elements of Chemistry. 
By M. V. Regnault. Translated from the French by T. Forrest 
Betton, M. D., and edited, with Notes, by James C. Booth, Melter 
and Refiner U. S. Mint, and Wm. L. Faber, Metallurgist and Mining 
Engineer. Illustrated by nearly 700 wood engravings. Comprising 
nearly 1500 pages. In two volumes, 8vo., cloth. . . . $7.50 



18 HEXBY CAREY BAIRD'S CATALOGUE. 

REID.— A Practical Treatise on the Manufacture of 
Portland Cement: 
By Hexey Reid, C. E. To which is added a Translation of iff. A. 
Lipowitz's Work, describing a New Method adopted in Germany for 
Manufacturing that Cement, by W. F. Beid. Illustrated by plates 
and wood engravings. 8to • . . . $5.00 

RIFFAXJLT, VERGNAUD, and TOUSSAINT.— A 
Practical Treatise on the Manufacture of Var- 
nishes. 
By MM. Biffaflt, Yehgxaud, and Tofssaixt. Revised and 
Edited by M. F. Malepeyee and Dr. Emil Wixcklee. Illustrated. 
In one volume, Svo. {In preparation.) 

RIFFAULT, VERGNAUD, and TOUSSAINT.— A 

Practical Treatise on the Manufacture of Colors 
for Painting : 

Containing the best Formulae and the Brocesses the Xewest and in 
most General Use. By M M. Riffault, Veegnaud, and Toussaint. 
Bevised and Edited by M. F. Malepeyee and Dr. Emil Wixcklee. 
Translated from the French by A. A. Fesquet, Chemist and Engi- 
neer. Illustrated by Engravings. In one volume, 650 pages, Svo. 

$7.50 

ROBINSON.— Explosions of Steam Boilers: 

How they are Caused, and how they may be Prevented. By J. B. 
ROBINSON, Steam Engineer. 12mo $1.25 

ROPER.— A Catechism of High Pressure or Non- 
Condensing Steam-Engines : 
Including the Modelling, Constructing, Running, and Management 
of Steam Engines and Steam Boilers. With Illustrations. By 
Stephen Bopeb, Engineer. Full bound tucks . . . $2.00 

ROSELEUR.— Galvanoplastic Manipulations : 

A Bractical Guide for the Gold and Silver Electro-plater and the 
Galvanoplastic Operator. Translated from the French of Alfeed 
Boselefe, Chemist, Brofessor of the Galvanoplastic Art, Manufactu- 
rer of Chemicals, Gold and Silver Electro-plater. By A. A. FESQUET, 
Chemist and Engineer. Illustrated by over 127 Engravings on wood. 

8vo., 495 pages. . $6.00 

7^- This Treatise is the fullest and by far the best on this subject ever 
published in the United States. 

SCHINZ — Researches on the Action of the Blast 
Furnace. 
By Chaeles Schinz. Translated from the German with the special 
permission of the Author by William H. Maw and Moeitz Mdl- 
LEE. With an Appendix written by the Author expressly for this . 
edition. Illustrated by seven plates, containing 28 figures. In one 
volume, 12mo. $4.00 



HENRY CAREY BAIRD'S CATALOGUE. 19 

SHAW.— Civil Architecture : 

Being a Complete Theoretical and Practical System of Building, con- 
taining the Fundamental Principles of the Art. By EDWARD Shaw, 
Architect. To Avhich is added a Treatise on Gothic Architecture, -etc. 
By Thomas W. Silloway and George M. Harding, Architects. 
The whole illustrated by One Hundred and Two quarto plates finely 
engraved on copper. Eleventh Edition. 4to., cloth. . $10.00 

SHLTrTK.— A Practical Treatise on Railway Curves 
and Location, for Young Engineers. 
By William F. Shuxk, Civil Engineer. 12mo. . . $2.00 

SLOAN.— American Houses : 

A variety of Original Designs for Rural Buildings. Illustrated by 26 
colored Engravings, with Descriptive References. By Samuel Seoax, 
Architect, author of the " Model Architect," etc., etc. Svo. $1.50 

SMEATOrT— Builder's Pocket Companion: 

Containing the Elements of Building, Surveying, and Architecture; 
with. Practical Rules and Instructions connected with the subject. 
By A. C. Smeaton, Civil Engineer, etc. In one volume, 12mo. $1.50 

SMITH.— A Manual of Political Economy. 

By E. Peshine Smith. A new Edition, to which is added a full 
Index. 12mo., cloth $1.25 

SMITH.— Parks and Pleasure Grounds: 

Or Practical Notes on Country Residences, Villas, Public Parks, and 
Gardens. By Charles H." J. Smith, Landscape Gardener and 
Garden Architect, etc., etc. 12mo. . • . . . $2.25 

SMITH.— The Dyer's Instructor: 

Comprising Practical Instructions in the Art of Dyeing Silk, Cotton, 
Wool, and Worsted, and Woollen Goods : containing nearly 800 
Receipts. To which is added a Treatise on the Art of Padding* ; and 
the Printing of Silk Warps, Skeins, and Handkerchiefs, and the 
various Mordants and Colors for the different styles of such work. 
By David Smith, Pattern Dyer. 12mo., cloth. . . . $3.00 

SMITH.— The Dyer's Instructor: 

Comprising Practical Instructions in the Art of Dyeing Silk, Cotton, 
Wool, and Worsted and Woollen Goods. Third Edition, with many 
additional Receipts for Dyeing the New Alkaline Blues and Night 
Greens, with Dyed Patterns affixed. 12uio., pp. 394, cloth. . $10.50 

STEWART.— The American System. 

Speeches on the Tariff Question, and on Internal Improvements, princi- 
pally delivered in the House of Representatives of the United States. 
By Andrew Stewart, late M. C. from Pennsylvania. With a Portrait, 
• and a Biographical Sketch. In one volume, 8vo., 407 pages. $3.00 



20 HEXRY CAEEY BAIRD'S CATALOGUE. 

STOKES. — Cabinet-maker's and Upholsterer's Com- 
panion : 

Comprising the Rudiments and Principles of Cabinet-making and Up- 
holstery, with Familiar Instructions, illustrated by Examples for 
attaining a Proficiency in the Art of Drawing, as applicable to Cabi- 
net-work ; the Processes of Yeneerini, Inlaying, and Buhl-work ; the 
Art of Dyeing and Staining Yv'ood, Pone, Tortoise Shell, etc. Direc- 
tions for Lackering, Japanning, and Yarnishing; to make French 
Polish ; to prepare the Best Glues, Cements, and Compositions, and a 
number of Receipts particularly useful for workmen generally. By 
J. Stokes. In one yolume, 12mo. With Illustrations. . " $1.1,5 

Strength and other Properties of Metals: 

Reports of Experiments on the Strength and other Properties of }.letals 
for Cannon. With a Description of the Machines for testing Metal"., 
and of the Classification of Cannon in seryice. By Officers of the Ord- 
nance Department U. S. Army. By authority of the Secretary of War. 
Illustrated by 25 Jarge stsel plates. In one yolume, 4to. . $10.00 

SULLIVAU.— Protection to Native Industry. 
By Sir Edvtaf.d Sullivan, Baronet, author of " Ten Chapters on 
Social Reforms." In one yolume, Svo $1.50 

Tables Showing the Weight of Round, Square, and 
Plat Bar Iron, Steel, etc., 
By Measurement. Cloth 63 

TAYLOR,.— Statistics of Coal : 
Including Mineral Bituminous Substances employed in Arts and 
Manufactures ; with their Geographical, Geological, and Commercial 
Distribution and Amount of Production and Consumption on the 
American Continent. With Incidental Statistics of the Iron Manu- 
facture. By R. C. Tayloe. Second edition, revised by S. S. Hal- 
demax. Illustrated by five Maps and many wood engravings. 8vo., 
cloth $10.00 

TEMPLETON.— The Practical Examinator on Steam 
and the Steam-Engine : 

With Instructive References relative thereto, arranged for the Use of 
Engineers, Students, and others. By Witt. Templeton, Engineer. 
12mo $1.25 

THOMAS.— The Modern Practice of Photography. 

By R. W. Thomas, F. C. S. 8vo., cloth 75 

THOMSON.— Freight Charges Calculator. 

By Andrew Thomson, Freight Agent. 24mo. . . . $1.25 

TURNING: Specimens of Fancy Turning Executed 
on the Hand or Foot Lathe: 

With Geometric, Oval, and Eccentric Chucks, and Elliptical Cutting 
Frame. By an Amateur. Illustrated by 30 exquisite Photographs. 
4to $3.00 



HENRY CAREY BAIRD'S CATALOGUE. 21 

Turner's (The) Companion: 

Containing Instructions in Concentric, Elliptic, and Eccentric Turn- 
ing : also various Plates of Chucks, Tools, and Instruments ; and Di- 
rections for using the Eccentric Cutter, Drill, Vertical Cutter, and 
Circular Rest ; -with Patterns and Instructions for working them. A 
new edition in one volume, 12mo. $1.50 

TJRBIN.— BRULL— A Practical Guide for Puddling 
Iron and Steel. 
By Ed. Urbin, Engineer of Arts and Manufactures. A Prize Essay 
read before the Association of Engineers, Graduate of the School of 
Mines, of Liege, Belgium, at the Meeting of 1865-6. To -which is added 
A Comparison of the Resisting Properties of Iron and Steel. 
By A. Brull. Translated from the French by A. A. Fesqlet, Che- 
mist and Engineer. In one volume, 8vo $1.00 

VAILE.— Galvanized Iron Cornice-Worker's Manual: 

Containing Instructions in Laying out the Different Mitres, and Ma- 
king Patterns for all kinds of Plain and Circular Work. Also, Tables 
of Weights, Areas and Circumferences of Circles, and other Mattet 
calculated to Benefit the Trade. By Charles A. Vaile, Superin- 
tendent "Richmond Cornice Worksj" Richmond, Indiana. Illustra- 
ted by 21 Plates. In one volume, 4to $5.00 

VILLE.— The School of Chemical Manures : 

Or, Elementary Principles in the Use of Fertilizing Agents. From the 
French of M. George Yille, by A. A. Fesquet, Chemist and Engi- 
neer. With Illustrations. In one volume, 12 mo. . . $1.25 

VOGDES — The Architect's and Builder's Pocket Com- 
panion and Price Book: 

Consisting of a Short but Comprehensive Epitome of Decimals, Duo- 
decimals, Geometry and Mensuration ; with Tables of U. S. Measures, 
Sizes, Weights, Strengths, etc., of Iron, Wood, Stone, and various 
other Materials, Quantities of Materials in Given Sizes, and Dimen- 
sions of Wood, Brick, and Stone; and a full and complete Bill of 
Prices for Carpenter's Work ; also, Rules tor Computing and Valuing 
Brick and Brick Work, Stone Work, Painting, Plastering, etc. By 
Frank W. Vogdes, Architect. Illustrated. Full bound in pocket- 
book form $2.00 

Bound in cloth. 1.50 

WARN.— The Sheet-Metal Worker's Instructor: 

For Zinc, Sheet-Iron, Copper, and Tin-Plate Workers, etc. Contain- 
ing a selection of Geometrical Problems; also, Practical and Simple 
Rules for describing the various Patterns required in the diiferent 
branches of the above Trades. By Reuben H. Warn, Practical Tin- 
plate Worker. To which is added an Appendix, containing Instruc- 
tions for Boiler Making, Mensuration of Surfaces and Solids, Rules for 
Calculating the Weights of diiferent Figures of Iron and Steel, Tables 
of the Weights of Iron, Steel, etc. Illustrated by 32 Plates and 37 
Wood Engravings. 8vo. $3.00 



22 HENRY CASEY BAIRD'S CATALOGUE. 

WATSON.— A Manual of the Hand-Lathe : 

Comprising Concise Directions for working Metals of all kinds, Ivory, 
Bone and Precious Woods ; Dyeing, Coloring, and French Polishing ; 
Inlaying by Veneers, and various methods practised to produce Elabo- 
rate work with Dispatch, and at Small Expense. By Egbert P. 
Watson, late of " The Scientific American," Author of " The Modern 
Practice of American Machinists and Engineers." Illustrated by 78 
Engravings $1.50 

WATSON.— The Modern Practice of American Ma- 
chinists and Engineers: 

Including the Construction, Application, and Use of Drills, Lathe 
Tools, Cutters for Boring Cylinders, and Hollow Work Generally, 
with the most Economical Speed for the same ; the Besults verified by 
Actual Practice at the Lathe, the Vice, and on the Floor. Together 
with Workshop Management, Economy of Manufacture, the Steam- 
Engine, Boilers, Gears, Belting, etc., etc. By Egbert P. Watson, 
late of the " Scientific American." Illustrated by 86 Engravings. In 
one volume, 12mo $2.50 

WATSON.— The Theory and Practice of the Art of 
Weaving by Hand and Power : 

With Calculations and Tables for the use of those connected with the 
Trade. By John Watson, Manufacturer ;md Practical Machine 
Maker. Illustrated by large Drawings of the best Power Looms. 
8vo. . • $7.50 

WEATHEHLY- Treatise on the Art of Boiling Su- 
gar, Crystallizing, Lozenge-making, Comfits, Gum 
Goods. 

12mo $2.00 

"WILL. — Tables for Qualitative Chemical Analysis. 
By Professor Heinrich Will, of Giessen, Germany. Seventh edi- 
tion. Translated by Charles F. Himes, Ph. D., Professor of Natu- 
ral Science, Dickinson College, Carlisle, Pa. . . . $1.50 

"WILLIAMS.— On Heat and Steam : 

Embracing New Views of Vaporization, Condensation, and Explosions. 
By Charles Wye Williams, A. I. C. E. Illustrated. 8vo. $3.50 

WOHLER.-A Hand-Book of Mineral Analysis. 

By F. Wohler, Professor of Chemistry in the University of Giittin- 
gen. Edited by Henry B. Nason, Professor of Chemistry in tbe 
Rensselaer Polytechnic Institute, Troy, New York. Illustrated. In 
one volume, 12mo $3 00 

WORSSAM — On Mechanical Saws: 
From the Transactions of the Society of Engineers, 1869. By S. W, 
WORSSAM, Jr. Illustrated by 18 large plates. 8vo. . . $D.oC 



HENRY CAREY BAIRD'S CATALOG GE. 23 



EEOENT ADDITIONS TO OUR LIST. 



AUERBACH. — Anthracen : Its Constitution, Properties, Man- 
ufacture, and Derivatives, including Artificial Alizarin, An- 
thrapurpurin, with their applications in Dyeing and Printing. 

By G. Auerbach. Translated and edited by Wm. Crookes, F. R. S. 
8vo. $5.00 

BECKETT.— Treatise on Clocks, Watches and Bells. 
By Sir Edmund Beckett, Bart. Illustrated. 12nio. . $1.75 

BARLOW. — The History and Principles of Weaving, by Hand 
and by Power. 

Several Hundred Illustrations. 8vo $10.00 

BOURNE. — Recent Improvements in the Steam Engine. 

By John Bourne, C. E. Illustrated. 16mo. . . . $1.50 
CLARK. — Fuel : Its Combustion and Economy. 

By D. Kinnear Clark, C. E. 144 Engravings. 12mo. . $2.25 
CRISTIANL— Perfumery and Kindred Arts. 

By R. S. Cristiani. 8vo. $5.00 

COLLENS.— The Eden of Labor, or the Christian Utopia. 

12rao. Paper, $1.00; Cloth, $1.25 

CUPPER.— The Universal Stair Builder. 

Illustrated by 29 plates. 4to $5.00 

COOLEY.— A Complete Practical Treatise on Perfumery. 

By A. J. Cooley. 12mo $1.50 

DAVIDSON.— A Practical Manual of House Painting, Grain- 
ing, Marbling and Sign Writing : 
With 9 Colored Illustrations of Woods and Marbles, and many Wood 
Engravings. 12mo. $3.00 

EDWARDS.— A Catechism of the Marine Steam Engine. 
By Emory Edwards. Illustrated. 12mo. . . . $2.00 

HASERICK.— The Secrets of he Art of D3 eing Wool, Cotton, 
and Linen : 

Including Bleaching and Coloring Wool and Cotton Hosiery and 
Random Yarns. By E. C. Haserick. Illustrated by 323 Dyed Pat- 
terns of the Yarns or Fabrics. 8vo $25.00 

HENRY.— The Early and Later History of Petroleum. 
By J. T. Henry. Illustrated. 8vo $4.50 



24 HENRY CAEEY BAIRD'S CATALOGUE. 

KELLOGG.— A New Monetary System. 
By Ed. Kellogg. Fifth Edition. Edited by Mary Kellogg 
Putnam. 12rno. Paper, $1.00; Cloth, .... §1.50 

KEMLO.- Watch Repairer's Hand-Book. 
Illustrated. 12mo. : . $1.25 

MORRIS. — Easy Rules for the Measurement of Earthworks by 
means of the Prismoidal Formula. 

By Elwood Morris, C. E. 8vo. $1.50 

McCULLOCH.— Distillation, Brewing and Malting. 

By J. C. McCulloch. 12mo $1.00 

NEVILLE.— Hydraulic Tables, Co-Efficients, and Formulae 
for Finding the Discharge of Water from Orifices, Notches, 
Weirs, Pipes, and Rivers. 

Illustrated. 12mo $5.00 

NICOLLS.— The Railway Builder. 

A Hand-book for Estimating the Probable Cost of American Railway 
Construction and Equipment. By Wm. J. Nicolls, C. E. Pocket- 
book Form $2.00 

NORMANDY.— The Commercial Hand-book of Chemical 
Analysis. 
By H. M. Noad, Ph. D. 12mo $5.00 

PROCTOR.— A Pocket-Book of Useful Tables and Formulae 
for Marine Engineers. 
By Frank Proctor. Pocket-book Form. . . . $2.00 

ROSE.— The Complete Practical Machinist : 
Embracing Lathe Work, Vise Work, Drills and Drilling, Taps and 
Dies, Hardening and Tempering, the Making and Use of Tools, etc., 
etc. By Joshua Bose. 130 Illustrations. 12mo. . . $2.50 

SLOAN. — Homestead Architecture. 
By Samuel Sloan, Architect. 200 Engravings. 8vo. . $3.50 

SYME. — Outlines of an Industrial Science. 
By David Syme. 12mo. . $2.00 

WARE. — The Coachmaker's Illustrated Hand-Book. 

Fully Illustrated. 8vo. $3.00 

WIGHT WICK.— Hints to Young Architects. 
Numerous Wood Cuts. 12mo $2.00 

WILSON.— First Principles of Political Economy. 
12mo $1.50 

WILSON.— A Treatise on Steam Boilers, their Strength, Con- 
struction, and Economical Working. 
By Bobt. Wilson. Illustrated. 12mo $2.50 



